Integrate project logger with MCP SDK ClientOptions and ServerOptions (#1067)

The MCP SDK v1.3.0 supports logger injection through `ClientOptions` and
`ServerOptions`, but the gateway was passing empty options
(`&sdk.ClientOptions{}`) or `nil`, leaving SDK operations invisible in
logs.

## Changes

**Client creation** (`internal/mcp/connection.go`)
- `newMCPClient()` now accepts `*logger.Logger` parameter
- Converts to `*slog.Logger` via `logger.NewSlogLoggerWithHandler()` 
- Passes to `sdk.ClientOptions.Logger`

**Server creation** (`internal/server/unified.go`,
`internal/server/routed.go`)
- Pass logger via `sdk.ServerOptions` in unified mode
- Pass logger via `sdk.ServerOptions` in routed/filtered servers

**Tests**
- Tests pass `nil` to disable SDK logging in test environments
- Added `TestNewMCPClientWithLogger` for validation

## Example

Before:
```go
sdk.NewClient(&sdk.Implementation{...}, &sdk.ClientOptions{})
sdk.NewServer(&sdk.Implementation{...}, nil)
```

After:
```go
sdk.NewClient(&sdk.Implementation{...}, &sdk.ClientOptions{
    Logger: logger.NewSlogLoggerWithHandler(log),
})
sdk.NewServer(&sdk.Implementation{...}, &sdk.ServerOptions{
    Logger: logger.NewSlogLoggerWithHandler(logUnified),
})
```

SDK internal operations now flow through the project's debug logging
system (`DEBUG=*` shows SDK activity).

> [!WARNING]
>
> <details>
> <summary>Firewall rules blocked me from connecting to one or more
addresses (expand for details)</summary>
>
> #### I tried to connect to the following addresses, but was blocked by
firewall rules:
>
> - `example.com`
> - Triggering command: `/tmp/go-build1436996487/b275/launcher.test
/tmp/go-build1436996487/b275/launcher.test
-test.testlogfile=/tmp/go-build1436996487/b275/testlog.txt
-test.paniconexit0 -test.timeout=10m0s -test.v=true o s.go
64/pkg/tool/linu_x004.c
credential.helpe/opt/hostedtoolcache/go/1.25.7/x64/pkg/tool/linux_amd64/vet`
(dns block)
> - `invalid-host-that-does-not-exist-12345.com`
> - Triggering command: `/tmp/go-build1436996487/b260/config.test
/tmp/go-build1436996487/b260/config.test
-test.testlogfile=/tmp/go-build1436996487/b260/testlog.txt
-test.paniconexit0 -test.timeout=10m0s -test.v=true go ac/hmac.go
x_amd64/asm --depth 2 REDACTED x_amd64/asm conf�� g_.a HEHYCbGHr
64/pkg/tool/linux_amd64/compile user.name` (dns block)
> - `nonexistent.local`
> - Triggering command: `/tmp/go-build1436996487/b275/launcher.test
/tmp/go-build1436996487/b275/launcher.test
-test.testlogfile=/tmp/go-build1436996487/b275/testlog.txt
-test.paniconexit0 -test.timeout=10m0s -test.v=true o s.go
64/pkg/tool/linu_x004.c
credential.helpe/opt/hostedtoolcache/go/1.25.7/x64/pkg/tool/linux_amd64/vet`
(dns block)
> - `slow.example.com`
> - Triggering command: `/tmp/go-build1436996487/b275/launcher.test
/tmp/go-build1436996487/b275/launcher.test
-test.testlogfile=/tmp/go-build1436996487/b275/testlog.txt
-test.paniconexit0 -test.timeout=10m0s -test.v=true o s.go
64/pkg/tool/linu_x004.c
credential.helpe/opt/hostedtoolcache/go/1.25.7/x64/pkg/tool/linux_amd64/vet`
(dns block)
> - `this-host-does-not-exist-12345.com`
> - Triggering command: `/tmp/go-build1436996487/b284/mcp.test
/tmp/go-build1436996487/b284/mcp.test
-test.testlogfile=/tmp/go-build1436996487/b284/testlog.txt
-test.paniconexit0 -test.timeout=10m0s -test.v=true -c=4 -nolocalimports
-importcfg /tmp/go-build180286792/b223/importcfg -pack
/home/REDACTED/work/gh-aw-mcpg/gh-aw-mcpg/internal/middleware/jqschema.go
64/pkg/include 64/s�� 64/src/runtime/cgo --global
ache/go/1.25.7/x64/pkg/tool/linu--64 pull.rebase` (dns block)
> - Triggering command: `/tmp/go-build2197604316/b284/mcp.test
/tmp/go-build2197604316/b284/mcp.test
-test.testlogfile=/tmp/go-build2197604316/b284/testlog.txt
-test.paniconexit0 -test.timeout=10m0s -test.v=true
ache/go/1.25.7/x64/src/runtime/c-p v5H2/gdzdyx1nTJ_thj3Av5H2
8085717/b189/` (dns block)
> - Triggering command: `/tmp/go-build1032557839/b284/mcp.test
/tmp/go-build1032557839/b284/mcp.test
-test.testlogfile=/tmp/go-build1032557839/b284/testlog.txt
-test.paniconexit0 -test.timeout=10m0s -test.v=true s
mn4I/VW84qF8_Uqs9FMGXmn4I x_amd64/compile` (dns block)
>
> If you need me to access, download, or install something from one of
these locations, you can either:
>
> - Configure [Actions setup
steps](https://gh.io/copilot/actions-setup-steps) to set up my
environment, which run before the firewall is enabled
> - Add the appropriate URLs or hosts to the custom allowlist in this
repository's [Copilot coding agent
settings](https://github.com/github/gh-aw-mcpg/settings/copilot/coding_agent)
(admins only)
>
> </details>

<!-- START COPILOT ORIGINAL PROMPT -->



<details>

<summary>Original prompt</summary>


----

*This section details on the original issue you should resolve*

<issue_title>[go-fan] Go Module Review:
modelcontextprotocol/go-sdk</issue_title>
<issue_description># 🐹 Go Fan Report: modelcontextprotocol/go-sdk

## Module Overview

The **modelcontextprotocol/go-sdk** is the official Go SDK for Model
Context Protocol servers and clients, maintained in collaboration with
Google. This SDK provides comprehensive support for building MCP servers
and clients in Go, including HTTP/SSE transport, stdio transport,
tool/resource/prompt registration, and session management.

**Repository**: https://github.com/modelcontextprotocol/go-sdk  
**Version Used**: v1.3.0 ✅ (Latest)  
**Last Updated**: 2026-02-18 (Today!)  
**Stars**: 3,875 ⭐

## Current Usage in gh-aw-mcpg

### Files & Import Statistics
- **Files**: 20 files (5 production + 15 test files)
- **Import Count**: 20 direct imports
- **Key APIs Used**:
- Server APIs: `NewServer()`, `AddTool()`, `NewStreamableHTTPHandler()`,
`StreamableHTTPOptions`
  - Client APIs: `NewClient()`, `Connect()`, `ListTools()`, `CallTool()`
- Transport APIs: `NewInMemoryTransports()`, StreamableHTTP with session
support

### Production Files
1. `internal/server/transport.go` - StreamableHTTP handler creation
2. `internal/server/unified.go` - Unified mode server implementation  
3. `internal/server/routed.go` - Routed mode server implementation
4. `internal/mcp/connection.go` - Client connections to backend MCP
servers
5. `internal/testutil/mcptest/` - Test infrastructure (3 files)

### Current Patterns

**Server Creation:**
```go
sdk.NewServer(&sdk.Implementation{
    Name:    "awmg-unified",
    Version: "1.0.0",
}, nil)  // ⚠️ No server options used
```

**Client Creation:**
```go
sdk.NewClient(&sdk.Implementation{
    Name:    "awmg",
    Version: version.Get(),
}, &sdk.ClientOptions{})  // ⚠️ Empty options
```

**StreamableHTTP (Good!):**
```go
&sdk.StreamableHTTPOptions{
    Stateless:      false,
    Logger:         logger.NewSlogLoggerWithHandler(logTransport),
    SessionTimeout: 30 * time.Minute,
}
```

## Research Findings

### Recent Updates (v1.3.0 - Released 2026-02-09)

The project is using the **latest version** of the SDK! v1.3.0 includes
significant improvements:

1. **✨ Schema Caching** - Dramatically improves performance in stateless
server scenarios
2. **🔧 Logger in ClientOptions** - Logging moved from deprecated
location to `ClientOptions`
3. **🛡️ GetError/SetError Export** - Better structured error handling
4. **🐛 Case-Insensitive HTTP Headers** - Fixed SSE Content-Type checking
bug
5. **⚡ Race Condition Fix** - Fixed logging race condition
6. **📋 HTTP 405 Compliance** - Added Allow header per RFC 9110

### Best Practices from SDK Maintainers

1. **Logger Integration**: Pass logger through `ClientOptions` and
`ServerOptions` for complete visibility
2. **Error Handling**: Use SDK's `GetError/SetError` methods for
structured error context
3. **Session Management**: Leverage `StreamableHTTP` with timeouts (✅
already doing this!)
4. **Schema Caching**: Automatic in v1.3.0, provides significant
performance gains

### SDK Features We're NOT Using

1. **Resources API** - Only test usage, no production resources exposed
2. **Prompts API** - Zero usage (could provide helpful templates)
3. **Completion API** - Zero usage
4. **Sampling API** - Zero usage (LLM integration)
5. **Extensions (SEP-2133)** - New capability for custom protocol
extensions
6. **Advanced Logging** - Logger only in transport, not in client/server
options
7. **Structured Error Types** - Custom HTTP errors instead of SDK types

## Improvement Opportunities

### 🏃 Quick Wins

#### 1. Add Logger to ClientOptions ⭐ HIGH PRIORITY
- **Current**: `&sdk.ClientOptions{}` (empty)
- **Fix**: Pass project logger to SDK
- **Benefit**: Unified logging across gateway and SDK operations
- **Effort**: 1-2 hours
- **Location**: `internal/mcp/connection.go:165`
- **Code**:
  ```go
  &sdk.ClientOptions{
      Logger: logger.NewSlogLoggerWithHandler(logClient),
  }
  ```

#### 2. Add Logger to ServerOptions ⭐ HIGH PRIORITY
- **Current**: `sdk.NewServer(..., nil)` (no options)
- **Fix**: Pass logger via server options
- **Benefit**: Better visibility into SDK server operations
- **Effort**: 1-2 hours
- **Locations**: `internal/server/unified.go:136`,
`internal/server/routed.go:187`

#### 3. Validate Schema Caching Performance
- **Current**: Automatic in v1.3.0 (good!)
- **Improvement**: Add metrics to quantify performance gains
- **Benefit**: Document actual performance improvements
- **Effort**: 2-3 hours

### ✨ Feature Opportunities

#### 1. Implement Resources API (Medium Complexity)
**Opportunity**: Expose gateway state as MCP resources

**Potential Resources**:
- `/config` - Current gateway configuration
- `/health` - Gateway health status
- `/metrics` - Performance metrics
- `/backends` - Backend server status
- `/sessions` - Active session information

**Benefit**: Clients can query gateway state using ...

</details>



<!-- START COPILOT CODING AGENT SUFFIX -->

- Fixes #1059

<!-- START COPILOT CODING AGENT TIPS -->
---

🔒 GitHub Advanced Security automatically protects Copilot coding agent
pull requests. You can protect all pull requests by enabling Advanced
Security for your repositories. [Learn more about Advanced
Security.](https://gh.io/cca-advanced-security)

Author: lpcox

internal/mcp/connection.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"io"
 	"log"
+	"log/slog"
 	"net/http"
 	"os"
 	"os/exec"
@@ -158,11 +159,18 @@ type Connection struct {
 }
 
 // newMCPClient creates a new MCP SDK client with standard implementation details
-func newMCPClient() *sdk.Client {
+// Pass nil for logger parameter to disable SDK logging (for tests)
+func newMCPClient(log *logger.Logger) *sdk.Client {
+	var slogLogger *slog.Logger
+	if log != nil {
+		slogLogger = logger.NewSlogLoggerWithHandler(log)
+	}
 	return sdk.NewClient(&sdk.Implementation{
 		Name:    "awmg",
 		Version: version.Get(),
-	}, &sdk.ClientOptions{})
+	}, &sdk.ClientOptions{
+		Logger: slogLogger,
+	})
 }
 
 // newHTTPConnection creates a new HTTP Connection struct with common fields
@@ -300,8 +308,8 @@ func NewConnection(ctx context.Context, serverID, command string, args []string,
 	logConn.Printf("Creating new MCP connection: command=%s, args=%v", command, sanitize.SanitizeArgs(args))
 	ctx, cancel := context.WithCancel(ctx)
 
-	// Create MCP client
-	client := newMCPClient()
+	// Create MCP client with logger
+	client := newMCPClient(logConn)
 
 	// Expand Docker -e flags that reference environment variables
 	// Docker's `-e VAR_NAME` expects VAR_NAME to be in the environment
@@ -506,8 +514,8 @@ func trySDKTransport(
 	transportName string,
 	createTransport transportConnector,
 ) (*Connection, error) {
-	// Create MCP client
-	client := newMCPClient()
+	// Create MCP client with logger
+	client := newMCPClient(logConn)
 
 	// Create transport using the provided connector
 	transport := createTransport(url, httpClient)

internal/mcp/connection_test.go

@@ -11,6 +11,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/github/gh-aw-mcpg/internal/logger"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -568,10 +569,17 @@ data: {"jsonrpc":"2.0","id":` + idStr + `,"result":{"tools":[]}}
 
 // TestNewMCPClient tests the newMCPClient helper function
 func TestNewMCPClient(t *testing.T) {
-	client := newMCPClient()
+	client := newMCPClient(nil)
 	require.NotNil(t, client, "newMCPClient should return a non-nil client")
 }
 
+// TestNewMCPClientWithLogger tests that newMCPClient accepts a logger
+func TestNewMCPClientWithLogger(t *testing.T) {
+	log := logger.New("test:client")
+	client := newMCPClient(log)
+	require.NotNil(t, client, "newMCPClient should return a non-nil client with logger")
+}
+
 // TestCreateJSONRPCRequest tests the createJSONRPCRequest helper function
 func TestCreateJSONRPCRequest(t *testing.T) {
 	tests := []struct {
@@ -687,7 +695,7 @@ func TestNewHTTPConnection(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
-	client := newMCPClient()
+	client := newMCPClient(nil)
 	url := "http://example.com/mcp"
 	headers := map[string]string{"Authorization": "test"}
 	httpClient := &http.Client{}

internal/server/routed.go

@@ -183,11 +183,13 @@ func CreateHTTPServerForRoutedMode(addr string, unifiedServer *UnifiedServer, ap
 func createFilteredServer(unifiedServer *UnifiedServer, backendID string) *sdk.Server {
 	logRouted.Printf("Creating filtered server: backend=%s", backendID)
 
-	// Create a new SDK server for this route
+	// Create a new SDK server for this route with logger
 	server := sdk.NewServer(&sdk.Implementation{
 		Name:    fmt.Sprintf("awmg-%s", backendID),
 		Version: "1.0.0",
-	}, nil)
+	}, &sdk.ServerOptions{
+		Logger: logger.NewSlogLoggerWithHandler(logRouted),
+	})
 
 	// Get tools for this backend from the unified server
 	tools := unifiedServer.GetToolsForBackend(backendID)

internal/server/unified.go

@@ -132,11 +132,13 @@ func NewUnified(ctx context.Context, cfg *config.Config) (*UnifiedServer, error)
 		enableDIFC:    cfg.EnableDIFC,
 	}
 
-	// Create MCP server
+	// Create MCP server with logger
 	server := sdk.NewServer(&sdk.Implementation{
 		Name:    "awmg-unified",
 		Version: "1.0.0",
-	}, nil)
+	}, &sdk.ServerOptions{
+		Logger: logger.NewSlogLoggerWithHandler(logUnified),
+	})
 
 	us.server = server