Adds public events endpoint and user tickets

Adds a public events endpoint that allows read-only access to all events.
Improves ticket management by adding support for user IDs as an identifier, alongside name and email.
This simplifies ticket creation for authenticated users and enhances security.
Also introduces an API endpoint to fetch tickets by user ID.

API_DOCUMENTATION.md

@@ -0,0 +1,56 @@
+# Events API Documentation
+
+## Public Events Endpoint
+
+### GET `/api/v1/events/public`
+
+Retrieve all events in the database with read-only access. No authentication required.
+
+**Authentication:** None required (public endpoint)
+
+**Headers:**
+```
+None required
+```
+
+**Query Parameters:**
+- None
+
+**Response:**
+```json
+[
+  {
+    "id": "event_id",
+    "wallet": "wallet_id",
+    "name": "Event Name",
+    "info": "Event description",
+    "closing_date": "2024-12-31",
+    "event_start_date": "2024-12-01",
+    "event_end_date": "2024-12-02",
+    "currency": "sat",
+    "amount_tickets": 100,
+    "price_per_ticket": 1000.0,
+    "time": "2024-01-01T00:00:00Z",
+    "sold": 0,
+    "banner": null
+  }
+]
+```
+
+**Example Usage:**
+```bash
+curl http://your-lnbits-instance/events/api/v1/events/public
+```
+
+**Notes:**
+- This endpoint allows read-only access to all events in the database
+- No authentication required (truly public endpoint)
+- Returns events ordered by creation time (newest first)
+- Suitable for public event listings or read-only integrations
+
+## Comparison with Existing Endpoints
+
+| Endpoint | Authentication | Scope | Use Case |
+|----------|---------------|-------|----------|
+| `/api/v1/events` | Invoice Key | User's wallets only | Private event management |
+| `/api/v1/events/public` | None | All events | Public event browsing |