fix: resolve CI lint/spell/snapshot issues

- Add nolint:gosec directive for intentional context.Background() in
  background goroutine (tool_update_check.go)
- Add GOWORK/Gowork to cspell dictionary (magefile.go references)
- Update TestUsage-azd.snap to include new build command

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: wbreza

cli/azd/.vscode/cspell.yaml

@@ -29,6 +29,8 @@ words:
   # CDN host name
   - gfgac2cmf7b8cuay
   - Getenv
+  - GOWORK
+  - Gowork
   - goversioninfo
   - OPENCODE
   - opencode

cli/azd/cmd/middleware/tool_update_check.go

@@ -155,6 +155,7 @@ func (m *ToolUpdateCheckMiddleware) triggerBackgroundCheckIfNeeded(ctx context.C
 		return
 	}
 
+	//nolint:gosec // G118 – intentional: goroutine outlives request; parent ctx is cancelled on return.
 	go func() {
 		defer func() {
 			if r := recover(); r != nil {

cli/azd/cmd/testdata/TestUsage-azd.snap

@@ -26,6 +26,7 @@ Commands
 
   Beta commands
     add         	: Add a component to your project.
+    build       	: Builds the application's code.
     extension   	: Manage azd extensions.
     hooks       	: Develop, test and run hooks for a project.
     infra       	: Manage your Infrastructure as Code (IaC).