⚡ Bolt: Optimize text/event-stream Content Type Check

[callmeradical]

💡 What: Replaced mime.ParseMediaType with strings.HasPrefix(strings.ToLower(...)) in cmd/sergeant-mcp-client/proxy.go when checking if the content type is text/event-stream.
🎯 Why: To prevent unnecessary memory allocations and parsing overhead in the proxy hot path, where checking the exact or prefix of a header using mime.ParseMediaType is too costly. The strings.ToLower ensures RFC compliance for case-insensitive headers.
📊 Impact: Eliminates a memory allocation per proxy response, reducing CPU overhead and garbage collection pressure in a hot path.
🔬 Measurement: Run go test ./... and go build ./... to ensure no functionality is broken.

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PR created automatically by Jules for task 9865136386637669174 started by @callmeradical

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[callmeradical]

Closing as a duplicate/superseded Jules proposal. The canonical implementation is merged in #316.

[google-labs-jules]

Closing as a duplicate/superseded Jules proposal. The canonical implementation is merged in #316.

Understood. Acknowledging that this work is now obsolete and stopping work on this task.