Replace String() calls with .toString()/.toLocaleString() per ast-grep rule

- Add formatError() helper in CLI to safely handle unknown error types
- Add uniqueTestId() helper for generating unique test identifiers
- Replace String(id) with id.toString() for database ID conversions
- Replace String(n) with n.toLocaleString() for user-facing number formatting
- Fix TypeScript errors in test files (undefined checks, unused variables)
- Update lint commands to include ast-grep scanning

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/api-server/src/procedures/me/api-tokens.ts

@@ -95,7 +95,7 @@ export const deleteApiToken = os.me.apiTokens.delete
   .handler(async ({ input, context }) => {
     const result = await context.db
       .deleteFrom("api_tokens")
-      .where("id", "=", String(input.tokenId))
+      .where("id", "=", input.tokenId.toString())
       .where("user_id", "=", context.user.id)
       .executeTakeFirst();