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.

internal/api/stale.go

@@ -7,9 +7,9 @@ import (
 
 	"github.com/go-chi/chi/v5"
 
-	"github.com/alexei/docker-watcher/internal/events"
-	"github.com/alexei/docker-watcher/internal/stale"
-	"github.com/alexei/docker-watcher/internal/store"
+	"github.com/alexei/tinyforge/internal/events"
+	"github.com/alexei/tinyforge/internal/stale"
+	"github.com/alexei/tinyforge/internal/store"
 )
 
 // listStaleContainers handles GET /api/containers/stale.