fix(import): persist object_key + metadata; add nav + logout session cleanup

- Import task: persist object_key, author, cover_url, genres, summary,
  book_status in PocketBase so the runner can fetch the file and write
  book metadata on completion
- Runner poll mode: pass task.ObjectKey instead of empty string
- Runner: write BookMeta + UpsertBook in Meilisearch after chapter ingest
  so imported books appear in catalogue and search
- Import UI: add author, cover URL, genres, summary, status fields; add
  AI tasks panel (chapter names, description, image gen, tagline) after
  import completes; add AI tasks button on each done task in the list
- Admin nav: add Notifications entry to sidebar (all 5 locales)
- Logout: delete user_sessions row on sign-out so sessions don't
  accumulate as phantoms after each login/logout cycle

backend/internal/backend/handlers_import.go

@@ -9,14 +9,20 @@ import (
 	"strings"
 	"time"
 
+	"github.com/libnovel/backend/internal/domain"
 	"github.com/libnovel/backend/internal/storage"
 )
 
 type importRequest struct {
-	Title     string `json:"title"`
-	FileName  string `json:"file_name"`
-	FileType  string `json:"file_type"` // "pdf" or "epub"
-	ObjectKey string `json:"object_key"` // MinIO path to uploaded file
+	Title       string   `json:"title"`
+	Author      string   `json:"author"`
+	CoverURL    string   `json:"cover_url"`
+	Genres      []string `json:"genres"`
+	Summary     string   `json:"summary"`
+	BookStatus  string   `json:"book_status"` // "ongoing" | "completed" | "hiatus"
+	FileName    string   `json:"file_name"`
+	FileType    string   `json:"file_type"`   // "pdf" or "epub"
+	ObjectKey   string   `json:"object_key"`  // MinIO path to uploaded file
 }
 
 type importResponse struct {
@@ -46,6 +52,17 @@ func (s *Server) handleAdminImport(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 		req.Title = r.FormValue("title")
+		req.Author = r.FormValue("author")
+		req.CoverURL = r.FormValue("cover_url")
+		req.Summary = r.FormValue("summary")
+		req.BookStatus = r.FormValue("book_status")
+		if g := r.FormValue("genres"); g != "" {
+			for _, s := range strings.Split(g, ",") {
+				if s = strings.TrimSpace(s); s != "" {
+					req.Genres = append(req.Genres, s)
+				}
+			}
+		}
 		req.FileName = r.FormValue("file_name")
 		req.FileType = r.FormValue("file_type")
 		analyzeOnly := r.FormValue("analyze") == "true"
@@ -115,7 +132,18 @@ func (s *Server) handleAdminImport(w http.ResponseWriter, r *http.Request) {
 		return -1
 	}, slug)
 
-	taskID, err := s.deps.Producer.CreateImportTask(r.Context(), slug, req.Title, req.FileType, objectKey, "")
+	taskID, err := s.deps.Producer.CreateImportTask(r.Context(), domain.ImportTask{
+		Slug:            slug,
+		Title:           req.Title,
+		Author:          req.Author,
+		CoverURL:        req.CoverURL,
+		Genres:          req.Genres,
+		Summary:         req.Summary,
+		BookStatus:      req.BookStatus,
+		FileType:        req.FileType,
+		ObjectKey:       objectKey,
+		InitiatorUserID: "",
+	})
 	if err != nil {
 		jsonError(w, http.StatusInternalServerError, "create import task: "+err.Error())
 		return