Update architecture and decisions docs with auth refinements

docs/development.md

@@ -26,12 +26,35 @@ go vet ./...
 go fmt ./...
 ```
 
+## Dependencies
+
+```bash
+go mod tidy     # after adding/removing imports
+```
+
 ## Config
 
-Server config is in `config.yaml` (symlink to `config.example.yaml` in development environment).
+Server config is loaded via viper from `config.yaml` (defaults in `internal/config/load.go`).
 
-```
+```yaml
 server:
     host: 0.0.0.0
     port: 10086
+
+database:
+    driver: sqlite3
+    sqlite:
+        path: data/mygo.db
+
+storage:
+    driver: local
+    local:
+        path: data/files
+
+jwt:
+    secret: changeme-in-production
+    access_ttl: 15m
+    refresh_ttl: 168h
 ```
+
+Environment variables use `MYGO_` prefix with underscore separators: `MYGO_SERVER_PORT=8080`, `MYGO_JWT_SECRET=...`