fix: Add missing closing brace for copilot target entry

The copilot entry in the targets record was missing its closing `},`
after merging with the gemini target branch, causing a parse error.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/targets/index.ts

@@ -64,6 +64,7 @@ export const targets: Record<string, TargetHandler> = {
     implemented: true,
     convert: convertClaudeToCopilot as TargetHandler<CopilotBundle>["convert"],
     write: writeCopilotBundle as TargetHandler<CopilotBundle>["write"],
+  },
   gemini: {
     name: "gemini",
     implemented: true,