feat(imap): add ImapIngestionProfile model, API, migration and UI

Replaces the simple binary attachment_filter string with a full
ingestion profiles system:

- Add FILE_TYPE_CATEGORIES dict to allowed_types.py (6 categories:
  pdf, office, opendocument, text, web, images) + DEFAULT_CATEGORIES
  / ALL_CATEGORIES + get_allowed_types_for_categories() helper
- Add ImapIngestionProfile model (id, name, description, owner_id,
  allowed_categories JSON, is_builtin)
- Update UserImapAccount: replace attachment_filter string with
  profile_id FK to imap_ingestion_profiles
- Migration 033: creates profiles table, seeds 2 built-in profiles
  (Documents Only, All Files), migrates attachment_filter → profile_id
- New /api/imap-profiles/ CRUD endpoints (list, create, get, update,
  delete) with category validation
- Register imap_profiles router in app/api/__init__.py
- Update imap_tasks.py: replace attachment_filter string param with
  profile-based allowed_categories; add _resolve_categories_for_profile()
- Update imap_accounts.py API to use profile_id instead of attachment_filter
- Update imap_accounts view to pass profiles + categories to template
- Full UI overhaul: profiles panel + profile create/edit modal with
  category checkboxes; profile selector in account modal
- 17 new tests (141 total), all passing

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

app/api/__init__.py

@@ -21,6 +21,7 @@ from app.api.files import router as files_router
 from app.api.google_drive import router as google_drive_router
 from app.api.i18n import router as i18n_router
 from app.api.imap_accounts import router as imap_accounts_router
+from app.api.imap_profiles import router as imap_profiles_router
 from app.api.integrations import router as integrations_router
 from app.api.logs import router as logs_router
 from app.api.mobile import router as mobile_router
@@ -83,6 +84,7 @@ router.include_router(onboarding_router)
 router.include_router(billing_router)
 router.include_router(pipelines_router)
 router.include_router(imap_accounts_router)
+router.include_router(imap_profiles_router)
 router.include_router(integrations_router)
 router.include_router(notifications_router)
 router.include_router(scheduled_jobs_router)