refactor(eslint): change unused vars rule to error and update error handling in services

- Update ESLint configuration to set `@typescript-eslint/no-unused-vars` from 'warn' to 'error' for stricter linting.
- Refactor error handling in various services to omit error variable in catch blocks for cleaner code.

src/api/integrations/chatbot/base-chatbot.service.ts

@@ -49,7 +49,7 @@ export abstract class BaseChatbotService<BotType = any, SettingsType = any> {
     try {
       JSON.parse(str);
       return true;
-    } catch (e) {
+    } catch {
       return false;
     }
   }