feat: Implement Garmin sync, login improvements, and utility scripts

README.md

@@ -0,0 +1,61 @@
+# FitTrack Garmin Sync Backend
+
+This project provides a backend service for synchronizing fitness data from Garmin Connect.
+
+## Getting Started
+
+...
+
+## Garmin Authentication
+
+To enable Garmin synchronization, you need to link your Garmin Connect account with this service. This is done via a dedicated login endpoint.
+
+### 1. Link your Garmin Account
+
+Send a `POST` request to the `/api/garmin/login` endpoint with your Garmin Connect username (email) and password.
+
+**Endpoint**: `POST /api/garmin/login`
+
+**Request Body (JSON)**:
+
+```json
+{
+  "username": "your_garmin_email@example.com",
+  "password": "your_garmin_password"
+}
+```
+
+**Example using `curl`**:
+
+```bash
+curl -X POST \
+  http://localhost:8000/api/garmin/login \
+  -H 'Content-Type: application/json' \
+  -d 
+  {
+    "username": "your_garmin_email@example.com",
+    "password": "your_garmin_password"
+  }
+```
+
+**Success Response (200 OK)**:
+
+```json
+{
+  "message": "Garmin account linked successfully."
+}
+```
+
+**Error Response (401 Unauthorized)**:
+
+```json
+{
+  "detail": "Invalid Garmin credentials provided."
+}
+```
+
+Upon successful login, your Garmin credentials and authentication tokens will be stored in the system. The system will handle token refreshes automatically to maintain continuous synchronization.
+
+### 2. Subsequent Synchronization
+
+Once linked, other Garmin synchronization endpoints (e.g., for activities, health metrics) will automatically use the stored and refreshed credentials to access your Garmin data. **These subsequent synchronization calls do not require any additional authentication headers from the client.**