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/docker.go

@@ -11,7 +11,7 @@ import (
 
 	"github.com/go-chi/chi/v5"
 
-	"github.com/alexei/docker-watcher/internal/store"
+	"github.com/alexei/tinyforge/internal/store"
 )
 
 // listProjectImages handles GET /api/projects/{id}/images.
@@ -220,7 +220,7 @@ func (s *Server) unusedImageStats(w http.ResponseWriter, r *http.Request) {
 }
 
 // pruneImages handles POST /api/docker/prune-images.
-// Only removes images that belong to Docker Watcher projects (not all system images).
+// Only removes images that belong to Tinyforge projects (not all system images).
 func (s *Server) pruneImages(w http.ResponseWriter, r *http.Request) {
 	if s.docker == nil {
 		respondError(w, http.StatusServiceUnavailable, "Docker is not available")