feat: auto-discover container images from registries

- Add ListImages() to registry interface, implement for Gitea
- Add owner field to registry config (needed for Gitea packages API)
- GET /api/registries/:id/images endpoint
- "Browse Images" button on Projects and Quick Deploy pages
- Image dropdown with registry grouping and search
- i18n support (EN/RU) for all new UI strings

internal/api/registries.go

@@ -17,6 +17,7 @@ type registryRequest struct {
 	URL   string `json:"url"`
 	Type  string `json:"type"`
 	Token string `json:"token"`
+	Owner string `json:"owner"`
 }
 
 // listRegistries handles GET /api/registries.
@@ -34,6 +35,7 @@ func (s *Server) listRegistries(w http.ResponseWriter, r *http.Request) {
 		URL       string `json:"url"`
 		Type      string `json:"type"`
 		HasToken  bool   `json:"has_token"`
+		Owner     string `json:"owner"`
 		CreatedAt string `json:"created_at"`
 		UpdatedAt string `json:"updated_at"`
 	}
@@ -46,6 +48,7 @@ func (s *Server) listRegistries(w http.ResponseWriter, r *http.Request) {
 			URL:       reg.URL,
 			Type:      reg.Type,
 			HasToken:  reg.Token != "",
+			Owner:     reg.Owner,
 			CreatedAt: reg.CreatedAt,
 			UpdatedAt: reg.UpdatedAt,
 		}
@@ -84,6 +87,7 @@ func (s *Server) createRegistry(w http.ResponseWriter, r *http.Request) {
 		URL:   req.URL,
 		Type:  req.Type,
 		Token: encToken,
+		Owner: req.Owner,
 	})
 	if err != nil {
 		respondError(w, http.StatusInternalServerError, "failed to create registry: "+err.Error())
@@ -125,6 +129,8 @@ func (s *Server) updateRegistry(w http.ResponseWriter, r *http.Request) {
 	if req.Type != "" {
 		updated.Type = req.Type
 	}
+	// Owner can be set to empty string intentionally, so always update it.
+	updated.Owner = req.Owner
 
 	// Only re-encrypt if a new token is provided.
 	if req.Token != "" {
@@ -265,3 +271,49 @@ func (s *Server) listRegistryTags(w http.ResponseWriter, r *http.Request) {
 
 	respondJSON(w, http.StatusOK, tags)
 }
+
+// listRegistryImages handles GET /api/registries/{id}/images.
+// Returns all container images available in the registry for the configured owner.
+func (s *Server) listRegistryImages(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+
+	reg, err := s.store.GetRegistryByID(id)
+	if err != nil {
+		if errors.Is(err, store.ErrNotFound) {
+			respondNotFound(w, "registry")
+			return
+		}
+		respondError(w, http.StatusInternalServerError, "failed to get registry: "+err.Error())
+		return
+	}
+
+	if reg.Owner == "" {
+		respondError(w, http.StatusBadRequest, "registry has no owner configured; set the owner in registry settings")
+		return
+	}
+
+	// Decrypt the token.
+	token := reg.Token
+	if token != "" {
+		decrypted, err := crypto.Decrypt(s.encKey, token)
+		if err != nil {
+			respondError(w, http.StatusInternalServerError, "failed to decrypt registry token")
+			return
+		}
+		token = decrypted
+	}
+
+	client, err := registry.NewClient(reg.Type, reg.URL, token)
+	if err != nil {
+		respondError(w, http.StatusBadRequest, "unsupported registry type: "+reg.Type)
+		return
+	}
+
+	images, err := client.ListImages(r.Context(), reg.Owner)
+	if err != nil {
+		respondError(w, http.StatusBadGateway, "failed to list images: "+err.Error())
+		return
+	}
+
+	respondJSON(w, http.StatusOK, images)
+}