fix: resolve repository mirroring status inconsistencies

- Fix 'already exists, skipping migration' logic that left repositories with incorrect 'imported' status
- Update database status to 'mirrored' when repository already exists in Gitea
- Add automatic startup repair to fix existing inconsistencies on container start
- Create diagnostic and repair tools for troubleshooting mirroring issues
- Ensure consistent state between Gitea and application database

Resolves issue where repositories showed successful mirroring logs but remained
in 'imported' status, causing UI confusion and preventing proper status tracking.

Changes:
- src/lib/gitea.ts: Fixed mirrorGithubRepoToGitea() and mirrorGitHubRepoToGiteaOrg()
- docker-entrypoint.sh: Added automatic repository status repair on startup
- scripts/investigate-repo.ts: New diagnostic tool for repository analysis
- scripts/repair-mirrored-repos.ts: New repair tool with startup mode support
- scripts/cleanup-duplicate-repos.ts: New tool for removing duplicate entries

Fixes multiple user reports of misleading 'successfully mirrored' logs
while repositories remained in inconsistent state.

docker-entrypoint.sh

@@ -232,6 +232,28 @@ else
   echo "❌ Startup recovery failed with exit code $RECOVERY_EXIT_CODE"
 fi
 
+# Run repository status repair to fix any inconsistent mirroring states
+echo "Running repository status repair..."
+if [ -f "dist/scripts/repair-mirrored-repos.js" ]; then
+  echo "Running repository repair using compiled script..."
+  bun dist/scripts/repair-mirrored-repos.js --startup
+  REPAIR_EXIT_CODE=$?
+elif [ -f "scripts/repair-mirrored-repos.ts" ]; then
+  echo "Running repository repair using TypeScript script..."
+  bun scripts/repair-mirrored-repos.ts --startup
+  REPAIR_EXIT_CODE=$?
+else
+  echo "Warning: Repository repair script not found. Skipping repair."
+  REPAIR_EXIT_CODE=0
+fi
+
+# Log repair result
+if [ $REPAIR_EXIT_CODE -eq 0 ]; then
+  echo "✅ Repository status repair completed successfully"
+else
+  echo "⚠️  Repository status repair completed with warnings (exit code $REPAIR_EXIT_CODE)"
+fi
+
 # Function to handle shutdown signals
 shutdown_handler() {
   echo "🛑 Received shutdown signal, forwarding to application..."