feat: rename Docker Watcher to Tinyforge

Rebrand the project as Tinyforge to reflect its evolution from a Docker
container watcher into a self-hosted mini CI/deployment platform.

Rename covers: Go module path, Docker labels, DB/config filenames,
JWT issuer, Dockerfile binary, docker-compose, CI workflows, frontend
i18n, README with static sites docs, and all code comments.

web/src/lib/sse.ts

@@ -1,7 +1,7 @@
 /**
  * SSE client helper with auto-reconnect and exponential backoff.
  *
- * Provides type-safe event handling for Docker Watcher's real-time
+ * Provides type-safe event handling for Tinyforge's real-time
  * event streams (deploy logs and instance status changes).
  */