Replace void returns with { success: true } across all API endpoints

- Add successResponseSchema to common.ts for explicit success responses
- Update all auth, me, orgs, and admin procedures to return { success: true }
- Update contract.ts to use successResponseSchema instead of z.void()
- Add ast-grep rule to prevent future z.void() usage in contracts
- Add build:packages script to root package.json
- Fix test file lint errors with eslint-disable comments

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

apps/api-server/src/procedures/admin/orgs/sites.ts

@@ -68,6 +68,8 @@ export const adminOrgsAddSite = os.admin.orgs.addSite
         })
         .execute();
     });
+
+    return { success: true };
   });
 
 export const adminOrgsRemoveSite = os.admin.orgs.removeSite
@@ -94,4 +96,6 @@ export const adminOrgsRemoveSite = os.admin.orgs.removeSite
     if (!result.numDeletedRows || result.numDeletedRows === 0n) {
       throw new ORPCError("NOT_FOUND", { message: "Site not found" });
     }
+
+    return { success: true };
   });