feat: add admin edit endpoint for server moderation (#315)

## Summary

Implements `PUT /v0/servers/{id}` admin edit endpoint to address part of
issue #182, providing an API-based solution for server moderation
without requiring direct database access.

- **New endpoint**: `PUT /v0/servers/{id}` for editing existing servers
- **Security**: Uses existing JWT auth with `PermissionActionEdit`
permissions
- **Anti-undelete protection**: Added `ServerStatusDeleted` status that
cannot be reverted
- **Full implementation**: Database, service, API, and comprehensive
test coverage

## Key Use Cases

- Mark malicious servers as `deleted` for takedown
- Update server metadata for moderation actions

Related to: https://github.com/modelcontextprotocol/registry/issues/182
(but that is not _done_ yet because we need admins to be able to login
(probably with #283), and need to add docs on how to do the takedown,
and probably guidelines on what we will/won't takedown)

internal/service/fake_service.go

@@ -146,6 +146,35 @@ func (s *fakeRegistryService) Publish(req model.PublishRequest) (*model.ServerRe
 	return &response, nil
 }
 
+// EditServer updates an existing server with new details (admin operation)
+func (s *fakeRegistryService) EditServer(id string, req model.PublishRequest) (*model.ServerResponse, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	// Validate the request
+	if err := model.ValidatePublisherExtensions(req); err != nil {
+		return nil, err
+	}
+
+	// Validate server name exists and format
+	if _, err := model.ParseServerName(req.Server); err != nil {
+		return nil, err
+	}
+
+	// Extract publisher extensions from request
+	publisherExtensions := model.ExtractPublisherExtensions(req)
+
+	// Update server in database
+	serverRecord, err := s.db.UpdateServer(ctx, id, req.Server, publisherExtensions)
+	if err != nil {
+		return nil, err
+	}
+
+	// Convert ServerRecord to ServerResponse format
+	response := serverRecord.ToServerResponse()
+	return &response, nil
+}
+
 // Close closes the in-memory database connection
 func (s *fakeRegistryService) Close() error {
 	return s.db.Close()

internal/service/registry_service.go

@@ -90,36 +90,36 @@ func validateMCPBPackage(host string) error {
 	if !isAllowed {
 		return fmt.Errorf("MCPB packages must be hosted on allowlisted providers (GitHub or GitLab). Host '%s' is not allowed", host)
 	}
-	
+
 	return nil
 }
 
 // validatePackage validates packages to ensure they meet requirements
 func validatePackage(pkg *model.Package) error {
 	registryType := strings.ToLower(pkg.RegistryType)
-	
+
 	// For direct download packages (mcpb or direct URLs)
-	if registryType == "mcpb" || 
-	   strings.HasPrefix(pkg.Identifier, "http://") || strings.HasPrefix(pkg.Identifier, "https://") {
+	if registryType == "mcpb" ||
+		strings.HasPrefix(pkg.Identifier, "http://") || strings.HasPrefix(pkg.Identifier, "https://") {
 		parsedURL, err := url.Parse(pkg.Identifier)
 		if err != nil {
 			return fmt.Errorf("invalid package URL: %w", err)
 		}
-		
+
 		host := strings.ToLower(parsedURL.Host)
-		
+
 		// For MCPB packages, validate they're from allowed hosts
 		if registryType == "mcpb" || strings.HasSuffix(strings.ToLower(pkg.Identifier), ".mcpb") {
 			return validateMCPBPackage(host)
 		}
-		
+
 		// For other URL-based packages, just ensure it's valid
 		if parsedURL.Scheme == "" || parsedURL.Host == "" {
 			return fmt.Errorf("package URL must be a valid absolute URL")
 		}
 		return nil
 	}
-	
+
 	// For registry-based packages, no special validation needed
 	// Registry types like "npm", "pypi", "docker-hub", "nuget" are all valid
 	return nil
@@ -254,3 +254,49 @@ func (s *registryServiceImpl) validateNoDuplicateRemoteURLs(ctx context.Context,
 
 	return nil
 }
+
+// EditServer updates an existing server with new details (admin operation)
+func (s *registryServiceImpl) EditServer(id string, req model.PublishRequest) (*model.ServerResponse, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	// Validate the request
+	if err := model.ValidatePublisherExtensions(req); err != nil {
+		return nil, err
+	}
+
+	// Validate server name exists and format
+	if _, err := model.ParseServerName(req.Server); err != nil {
+		return nil, err
+	}
+
+	// Validate all packages
+	for _, pkg := range req.Server.Packages {
+		if err := validatePackage(&pkg); err != nil {
+			return nil, fmt.Errorf("validation failed: %w", err)
+		}
+	}
+
+	// Validate reverse-DNS namespace matching for remote URLs
+	if err := model.ValidateRemoteNamespaceMatch(req.Server); err != nil {
+		return nil, err
+	}
+
+	// Check for duplicate remote URLs
+	if err := s.validateNoDuplicateRemoteURLs(ctx, req.Server); err != nil {
+		return nil, err
+	}
+
+	// Extract publisher extensions from request
+	publisherExtensions := model.ExtractPublisherExtensions(req)
+
+	// Update server in database
+	serverRecord, err := s.db.UpdateServer(ctx, id, req.Server, publisherExtensions)
+	if err != nil {
+		return nil, err
+	}
+
+	// Convert ServerRecord to ServerResponse format
+	response := serverRecord.ToServerResponse()
+	return &response, nil
+}

internal/service/service.go

@@ -6,8 +6,10 @@ import "github.com/modelcontextprotocol/registry/internal/model"
 type RegistryService interface {
 	// List retrieves servers with extension wrapper format
 	List(cursor string, limit int) ([]model.ServerResponse, string, error)
-	// GetByID retrieves a single server by registry metadata ID with extension wrapper format  
+	// GetByID retrieves a single server by registry metadata ID with extension wrapper format
 	GetByID(id string) (*model.ServerResponse, error)
 	// Publish publishes a server with separated extensions
 	Publish(req model.PublishRequest) (*model.ServerResponse, error)
+	// EditServer updates an existing server with new details
+	EditServer(id string, req model.PublishRequest) (*model.ServerResponse, error)
 }