feat: implement structured logging for server and client

Server:
- Add pino and pino-http for structured logging
- Create @Logged class decorator using Proxy pattern for automatic method logging
- Add pino redact config for sensitive data (password, token, etc.)
- Move AuthMiddleware to controllers folder (per architecture diagram)
- Add LoggingMiddleware for HTTP request logging
- Replace console.log/error with structured logger in controllers and app.ts
- Decorate all repositories and GPTAdapter with @Logged

Client:
- Add react-native-logs with namespaced loggers (apiLogger, storeLogger)
- Add request/response logging to ApiClient with duration tracking

CLAUDE.md

@@ -47,6 +47,8 @@ npm run start -w @caldav/server        # Run compiled server (port 3000)
 | | Mongoose | ODM |
 | | GPT (OpenAI) | AI/LLM for chat |
 | | JWT | Authentication |
+| | pino / pino-http | Structured logging |
+| | react-native-logs | Client-side logging |
 | Planned | iCalendar | Event export/import |
 
 ## Architecture
@@ -83,9 +85,12 @@ src/
 │   ├── EventConfirmDialog.tsx  # AI-proposed event confirmation modal
 │   └── ProposedEventCard.tsx   # Chat event proposal (uses EventCardBase + confirm/reject buttons)
 ├── Themes.tsx                  # Centralized color/theme definitions
+├── logging/
+│   ├── index.ts                # Re-exports
+│   └── logger.ts               # react-native-logs config (apiLogger, storeLogger)
 ├── services/
 │   ├── index.ts                # Re-exports all services
-│   ├── ApiClient.ts            # HTTP client (get, post, put, delete)
+│   ├── ApiClient.ts            # HTTP client with request logging (get, post, put, delete)
 │   ├── AuthService.ts          # login(), register(), logout(), refresh()
 │   ├── EventService.ts         # getAll(), getById(), getByDateRange(), create(), update(), delete()
 │   └── ChatService.ts          # sendMessage(), confirmEvent(), rejectEvent(), getConversations(), getConversation()
@@ -103,12 +108,16 @@ src/
 ```
 src/
 ├── app.ts                    # Entry point, DI setup, Express config
-├── controllers/              # Request handlers
+├── controllers/              # Request handlers + middleware (per architecture diagram)
 │   ├── AuthController.ts     # login(), register(), refresh(), logout()
 │   ├── ChatController.ts     # sendMessage(), confirmEvent(), rejectEvent(), getConversations(), getConversation()
-│   └── EventController.ts    # create(), getById(), getAll(), getByDateRange(), update(), delete()
-├── middleware/
-│   └── AuthMiddleware.ts     # authenticate() - JWT validation
+│   ├── EventController.ts    # create(), getById(), getAll(), getByDateRange(), update(), delete()
+│   ├── AuthMiddleware.ts     # authenticate() - JWT validation
+│   └── LoggingMiddleware.ts  # httpLogger - pino-http request logging
+├── logging/
+│   ├── index.ts              # Re-exports
+│   ├── logger.ts             # pino config with redact for sensitive data
+│   └── Logged.ts             # @Logged() class decorator for automatic method logging
 ├── routes/                   # API endpoint definitions
 │   ├── index.ts              # Combines all routes under /api
 │   ├── auth.routes.ts        # /api/auth/*
@@ -239,6 +248,32 @@ const Schema = new Schema<Doc, Model<Doc, {}, {}, IdVirtual>, {}, {}, IdVirtual>
 
 Repositories use `doc.toJSON() as unknown as Type` casting (required because Mongoose's TypeScript types don't reflect virtual fields in toJSON output).
 
+### Logging
+
+Structured logging with pino (server) and react-native-logs (client).
+
+**Server Logging:**
+- `pino` with `pino-pretty` for development, JSON in production
+- `pino-http` middleware logs all HTTP requests (method, path, status, duration)
+- `@Logged()` class decorator for automatic method logging on repositories and services
+- Sensitive data (password, token, etc.) automatically redacted via pino's `redact` config
+
+**@Logged Decorator Pattern:**
+```typescript
+@Logged("MongoEventRepository")
+export class MongoEventRepository implements EventRepository { ... }
+
+@Logged("GPTAdapter")
+export class GPTAdapter implements AIProvider { ... }
+```
+
+The decorator uses a Proxy to intercept method calls lazily, preserves sync/async nature, and logs start/completion/failure with duration.
+
+**Client Logging:**
+- `react-native-logs` with namespaced loggers (apiLogger, storeLogger)
+- ApiClient logs all requests with method, endpoint, status, duration
+- Log level: debug in __DEV__, warn in production
+
 ## MVP Feature Scope
 
 ### Must-Have
@@ -274,6 +309,8 @@ JWT_EXPIRES_IN=1h
 MONGODB_URI=mongodb://root:mongoose@localhost:27017/calchat?authSource=admin
 OPENAI_API_KEY=sk-proj-...
 USE_TEST_RESPONSES=false    # true = static test responses, false = real GPT AI
+LOG_LEVEL=debug             # debug | info | warn | error | fatal
+NODE_ENV=development        # development = pretty logs, production = JSON
 ```
 
 ## Current Implementation Status
@@ -299,6 +336,8 @@ USE_TEST_RESPONSES=false    # true = static test responses, false = real GPT AI
   - `ChatRepository` interface: updateMessage() added for respondedAction tracking
   - `GPTAdapter`: Full implementation with OpenAI GPT (gpt-5-mini model), function calling for calendar operations
   - `ai/utils/`: Provider-agnostic shared utilities (systemPrompt, toolDefinitions, toolExecutor, eventFormatter)
+  - `logging/`: Structured logging with pino, pino-http middleware, @Logged decorator
+  - All repositories and GPTAdapter decorated with @Logged for automatic method logging
 - **Stubbed (TODO):**
   - `AuthMiddleware.authenticate()`: Currently uses fake user for testing
   - `AuthController`: refresh(), logout()
@@ -323,7 +362,7 @@ USE_TEST_RESPONSES=false    # true = static test responses, false = real GPT AI
   - KeyboardAvoidingView for proper keyboard handling (iOS padding, Android height)
   - Auto-scroll to end on new messages and keyboard show
   - keyboardDismissMode="interactive" and keyboardShouldPersistTaps="handled"
-- `ApiClient`: get(), post(), put(), delete() implemented
+- `ApiClient`: get(), post(), put(), delete() implemented with request/response logging
 - `EventService`: getAll(), getById(), getByDateRange(), create(), update(), delete() - fully implemented
 - `ChatService`: sendMessage(), confirmEvent(), rejectEvent(), getConversations(), getConversation() - fully implemented with cursor pagination
 - `EventCardBase`: Shared base component with event layout (header, date/time/recurring icons, description) - used by both EventCard and ProposedEventCard