fix: Manga import chapter population, cover caching, and series bulk actions (#115)

* fix: Manga import chapter population, cover caching, and series bulk actions

Manga imported via MangaDex or MAL all showed placeholder cover images
and 0/0 issues because: (1) cover art was never downloaded to local
cache during import, and (2) MangaDex chapter API filtered by English
only — most popular manga had English translations DMCA'd, returning 0
chapters. The `if chapters:` guard then silently skipped Total/Have.

Changes:
- Add get_total_chapter_count() to mangadex.py that calls the aggregate
  endpoint WITHOUT translatedLanguage[] filter for accurate totals
- Extract shared _populate_manga_chapters() helper eliminating ~70 lines
  of duplicated code between addMangaToDB() and addMangaToDB_MAL()
- Multi-source chapter population: language-filtered → unfiltered
  aggregate → MAL num_chapters → explicit 0 (never NULL)
- Cache cover images locally via helpers.getImage() in both import paths
- Fix myanimelist.py truthiness bug where num_chapters=0 became None
- Add bulk selection (checkboxes) to SeriesTable with action bar
- Add POST /series/bulk-delete, bulk-pause, bulk-resume endpoints
- Add useBulkDeleteSeries, useBulkPauseSeries, useBulkResumeSeries hooks

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix: Address code review findings — row selection, input validation, raw SQL

- Use getRowId to key row selection by ComicID instead of positional
  index, preventing wrong-series bulk operations after sort/filter
- Reset confirmDelete state when selection changes to prevent stale
  confirmation targeting unintended series
- Add _validate_bulk_ids() shared helper with: max 100 IDs cap, string
  type validation, dict body type guard
- Replace raw text() SQL with SQLAlchemy table object query
- Remove dead ternary in bulk action bar count display

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: frankieramirez

comicarr/app/series/router.py

@@ -95,6 +95,80 @@ def resume_series(comic_id: str, ctx: AppContext = Depends(get_context)):
     return series_service.resume_comic(ctx, comic_id)
 
 
+# ---------------------------------------------------------------------------
+# Bulk series operations
+# ---------------------------------------------------------------------------
+
+MAX_BULK_IDS = 100
+
+
+def _validate_bulk_ids(request_body):
+    """Validate and extract IDs from a bulk operation request body."""
+    if not isinstance(request_body, dict):
+        return None, JSONResponse(status_code=422, content={"detail": "Request body must be a JSON object"})
+    ids = request_body.get("ids")
+    if not ids or not isinstance(ids, list):
+        return None, JSONResponse(status_code=400, content={"detail": "Missing ids array"})
+    if len(ids) > MAX_BULK_IDS:
+        return None, JSONResponse(
+            status_code=422, content={"detail": "Maximum %d IDs per bulk operation" % MAX_BULK_IDS}
+        )
+    if not all(isinstance(i, str) and i.strip() for i in ids):
+        return None, JSONResponse(status_code=422, content={"detail": "All IDs must be non-empty strings"})
+    return ids, None
+
+
+@router.post("/series/bulk-delete", dependencies=[Depends(require_session)])
+def bulk_delete_series(
+    request_body: dict = None,
+    ctx: AppContext = Depends(get_context),
+):
+    """Delete multiple series at once."""
+    ids, error = _validate_bulk_ids(request_body)
+    if error:
+        return error
+
+    results = []
+    for comic_id in ids:
+        result = series_service.delete_comic(ctx, comic_id)
+        results.append({"id": comic_id, "success": result.get("success", False)})
+
+    succeeded = sum(1 for r in results if r["success"])
+    return {"success": succeeded > 0, "deleted": succeeded, "total": len(ids), "results": results}
+
+
+@router.post("/series/bulk-pause", dependencies=[Depends(require_session)])
+def bulk_pause_series(
+    request_body: dict = None,
+    ctx: AppContext = Depends(get_context),
+):
+    """Pause multiple series at once."""
+    ids, error = _validate_bulk_ids(request_body)
+    if error:
+        return error
+
+    for comic_id in ids:
+        series_service.pause_comic(ctx, comic_id)
+
+    return {"success": True, "count": len(ids)}
+
+
+@router.post("/series/bulk-resume", dependencies=[Depends(require_session)])
+def bulk_resume_series(
+    request_body: dict = None,
+    ctx: AppContext = Depends(get_context),
+):
+    """Resume multiple series at once."""
+    ids, error = _validate_bulk_ids(request_body)
+    if error:
+        return error
+
+    for comic_id in ids:
+        series_service.resume_comic(ctx, comic_id)
+
+    return {"success": True, "count": len(ids)}
+
+
 @router.post("/series/{comic_id}/refresh", dependencies=[Depends(require_session)])
 def refresh_series(comic_id: str, ctx: AppContext = Depends(get_context)):
     """Refresh series metadata from provider."""