Bug fix: Do not call CheckHealth when authenticating with API keys (#232)

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## What was changed
- WISOTT
- Note: This bug fix was an unfortunate regression that was introduced
with
[this](#203).
This intends on fixing that.

## Why?
- Bug fix!

## Checklist
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1. Closes <!-- add issue number here -->

2. How was this tested:
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3. Any docs updates needed?
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Author: Shivs11

internal/controller/clientpool/clientpool.go

@@ -261,9 +261,15 @@ func (cp *ClientPool) DialAndUpsertClient(clientOpts sdkclient.Options, clientPo
 		return nil, err
 	}
 
-	if _, err := c.CheckHealth(context.Background(), &sdkclient.CheckHealthRequest{}); err != nil {
-		c.Close()
-		return nil, fmt.Errorf("temporal server health check failed: %w", err)
+	// Skip health check for API key auth — CheckHealth is a system-level
+	// (non-namespace-scoped) RPC that fails with namespace-scoped API keys
+	// on Temporal Cloud. This is safe because client.Dial already calls
+	// GetSystemInfo internally, which is a superset of CheckHealth.
+	if clientAuth.mode != AuthModeAPIKey {
+		if _, err := c.CheckHealth(context.Background(), &sdkclient.CheckHealthRequest{}); err != nil {
+			c.Close()
+			return nil, fmt.Errorf("temporal server health check failed: %w", err)
+		}
 	}
 
 	cp.mux.Lock()