task 6: narrow service interfaces in Server and Middleware

Split Server struct to accept narrow service interfaces instead of fat
composites (MediaService, AdminService). Each handler now depends only on
its specific slice (MediaBrowseService, MediaWriteService, etc.).

Split Middleware to depend on a narrow UserStore interface instead of full
repository.Store. Updated all constructors, call sites, and tests.

Added negative tests for nil AdminService and ProgressService returning
501 Not Implemented.

References task 6.

1 files changed, 26 insertions, 6 deletions

diff --git a/internal/api/server.go b/internal/api/server.go
index f934a56..87e2471 100644
--- a/internal/api/server.go
+++ b/internal/api/server.go
@@ -21,7 +21,12 @@ type Server struct {
 	sm          *auth.SessionManager
 	cfg         *internal.Config
 	mux         *http.ServeMux
-	mediaSvc    service.MediaService
+	browseSvc   service.MediaBrowseService
+	writeSvc    service.MediaWriteService
+	shareSvc    service.MediaShareService
+	tagSvc      service.MediaTagService
+	favSvc      service.MediaFavoriteService
+	noteSvc     service.MediaNoteService
 	adminSvc    service.AdminService
 	progressSvc service.ProgressService
 	authSvc     service.AuthService
@@ -32,20 +37,25 @@ type Server struct {
 }
 
 // NewServer creates a Server with routes.
-// If mediaSvc, adminSvc, progressSvc, or authSvc are nil, their respective routes return 501.
+// If any service argument is nil, its respective routes return 501.
 func NewServer(
 	store repository.Store,
 	hasher auth.Hasher,
 	sm *auth.SessionManager,
 	cfg *internal.Config,
-	mediaSvc service.MediaService,
+	browseSvc service.MediaBrowseService,
+	writeSvc service.MediaWriteService,
+	shareSvc service.MediaShareService,
+	tagSvc service.MediaTagService,
+	favSvc service.MediaFavoriteService,
+	noteSvc service.MediaNoteService,
 	adminSvc service.AdminService,
 	progressSvc service.ProgressService,
 	authSvc service.AuthService,
 	staticFS http.FileSystem,
 	remuxer probe.Remuxer,
 ) *Server {
-	return NewServerWithLogger(store, hasher, sm, cfg, mediaSvc, adminSvc, progressSvc, authSvc, staticFS, remuxer, slog.Default())
+	return NewServerWithLogger(store, hasher, sm, cfg, browseSvc, writeSvc, shareSvc, tagSvc, favSvc, noteSvc, adminSvc, progressSvc, authSvc, staticFS, remuxer, slog.Default())
 }
 
 // NewServerWithLogger creates a Server with routes and an injected logger.
@@ -54,7 +64,12 @@ func NewServerWithLogger(
 	hasher auth.Hasher,
 	sm *auth.SessionManager,
 	cfg *internal.Config,
-	mediaSvc service.MediaService,
+	browseSvc service.MediaBrowseService,
+	writeSvc service.MediaWriteService,
+	shareSvc service.MediaShareService,
+	tagSvc service.MediaTagService,
+	favSvc service.MediaFavoriteService,
+	noteSvc service.MediaNoteService,
 	adminSvc service.AdminService,
 	progressSvc service.ProgressService,
 	authSvc service.AuthService,
@@ -74,7 +89,12 @@ func NewServerWithLogger(
 		sm:          sm,
 		cfg:         cfg,
 		mux:         http.NewServeMux(),
-		mediaSvc:    mediaSvc,
+		browseSvc:   browseSvc,
+		writeSvc:    writeSvc,
+		shareSvc:    shareSvc,
+		tagSvc:      tagSvc,
+		favSvc:      favSvc,
+		noteSvc:     noteSvc,
 		adminSvc:    adminSvc,
 		progressSvc: progressSvc,
 		authSvc:     authSvc,