Fix BASE_URL config loading, add tasks/projects; robust .env path resolution

- Config: try ENV_FILE, .env, ../.env for loading; trim trailing slash from BaseURL
- Log BASE_URL at server startup for verification
- .env.example: document BASE_URL
- Tasks, projects, tags, migrations and related API/handlers

Made-with: Cursor

.env.example

@@ -11,8 +11,11 @@ JWT_SECRET=dev-secret-change-me
 SERVER_PORT=8080
 ENV=development
 
-# Base URL (used for public iCal feed URLs; defaults to http://localhost:$SERVER_PORT)
-# BASE_URL=https://api.example.com
+# Base URL for iCal feed URLs and availability URLs.
+# Defaults to http://localhost:$SERVER_PORT if unset.
+# Set to your public API URL for Google Calendar and external subscriptions.
+# Example: BASE_URL=https://api.example.com
+BASE_URL=http://localhost:8080
 
 # CORS (comma-separated origins; defaults to localhost:5173 for dev)
 # CORS_ORIGINS=https://app.example.com,https://www.example.com