refactor(api): rename ScanEbooks to ScanLibrary for clarity

- Rename ScanEbooks method to ScanLibrary to reflect generic media scanning

- Rename ScanEbooksRequest to ScanLibraryRequest

- Update route handlers in scanner.go and library.go

- Rename scan_ebooks.md to scan_library.md

- No breaking changes: API endpoint remains POST /api/scanner/scan

internal/handlers/ebook.go

@@ -69,15 +69,15 @@ func SetupRoutes(g *echo.Group, db *database.Queries, connManager *wsync.Connect
 	return NewHandler(db, connManager)
 }
 
-// ScanEbooksRequest represents the request for scanning ebooks
-type ScanEbooksRequest struct {
+// ScanLibraryRequest represents the request for scanning a library
+type ScanLibraryRequest struct {
 	FolderPaths []string `json:"folder_paths,omitempty"`
 	LibraryID   string   `json:"library_id,omitempty"`
 }
 
-// ScanEbooks handles POST /api/scanner/scan (now runs in background)
-func (h *Handler) ScanEbooks(c echo.Context) error {
-	var req ScanEbooksRequest
+// ScanLibrary handles POST /api/scanner/scan (now runs in background)
+func (h *Handler) ScanLibrary(c echo.Context) error {
+	var req ScanLibraryRequest
 
 	// Check if scan_request is set in context (from library scan route)
 	if scanReq, ok := c.Get("scan_request").(map[string]interface{}); ok {
@@ -160,7 +160,7 @@ func (h *Handler) StartScanner(c echo.Context) error {
 	h.mu.Lock()
 	defer h.mu.Unlock()
 
-	var req ScanEbooksRequest
+	var req ScanLibraryRequest
 	if err := c.Bind(&req); err != nil {
 		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid request"})
 	}