feat(logging): add comprehensive logging to all API routes (Phase 4)

Applied withLogging() wrapper to all 24 API routes for consistent logging:

Process Control Routes:
- Start/stop/restart individual processes
- Start-all/stop-all/restart-all batch operations

Signal Routes:
- Signal individual processes
- Signal all processes
- Signal process groups

Group Management Routes:
- Start/stop/restart process groups
- Signal operations for groups

Configuration Routes:
- Get all configs (GET)
- Reload configuration (POST)
- Add/remove process groups (POST/DELETE)

Log Routes:
- Read main supervisord log
- Read process stdout/stderr logs
- Clear process logs (individual and all)

System Routes:
- Get system info
- Get all processes info
- Get individual process info
- Send stdin to process

All routes now include:
- Request/response logging with timing
- Automatic error handling and correlation IDs
- X-Request-ID header propagation
- Consistent metadata in responses

Also fixed Next.js 16 deprecation:
- Moved experimental.serverComponentsExternalPackages to serverExternalPackages

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/api/supervisor/groups/[name]/start/route.ts

@@ -1,30 +1,24 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { createSupervisorClient } from '@/lib/supervisor/client';
+import { withLogging } from '@/lib/utils/api-logger';
 
 interface RouteParams {
   params: Promise<{ name: string }>;
 }
 
-// POST - Start all processes in a group
-export async function POST(request: NextRequest, { params }: RouteParams) {
-  try {
-    const { name } = await params;
-    const body = await request.json().catch(() => ({}));
-    const wait = body.wait ?? true;
+export const POST = withLogging(async (request: NextRequest, { params }: RouteParams) => {
+  const { name } = await params;
+  const body = await request.json().catch(() => ({}));
+  const wait = body.wait ?? true;
 
-    const client = createSupervisorClient();
-    const results = await client.startProcessGroup(name, wait);
+  const client = createSupervisorClient();
+  const results = await client.startProcessGroup(name, wait);
 
-    return NextResponse.json({
-      success: true,
-      message: `Started process group: ${name}`,
-      results,
-    });
-  } catch (error: any) {
-    console.error('Supervisor start process group error:', error);
-    return NextResponse.json(
-      { error: error.message || 'Failed to start process group' },
-      { status: 500 }
-    );
-  }
-}
+  return NextResponse.json({
+    success: true,
+    message: `Started process group: ${name}`,
+    results,
+    groupName: name,
+    wait,
+  });
+}, 'startProcessGroup');