feat(i18n): localize admin files page (filemanager.html)

Replace all hardcoded English strings in the admin file manager
template with _() translation calls and add 47 new admin_files.*
keys to en.json.

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

frontend/translations/en.json

@@ -149,6 +149,53 @@
   "admin_plans.stripe_wizard_text": "Stripe Setup Wizard",
   "admin_plans.subheading": "Manage subscription plans shown on the public pricing page.",
   "admin_plans.table_aria_label": "Subscription plans",
+  "admin_files.admin_only_badge": "Admin Only",
+  "admin_files.aria_breadcrumb": "Breadcrumb",
+  "admin_files.badge_delta_detected": "Delta detected",
+  "admin_files.badge_duplicate": "dup",
+  "admin_files.badge_in_db": "in DB",
+  "admin_files.badge_on_disk": "on disk",
+  "admin_files.breadcrumb_workdir": "workdir",
+  "admin_files.btn_download": "Download",
+  "admin_files.col_actions": "Actions",
+  "admin_files.col_db": "DB",
+  "admin_files.col_health": "Health",
+  "admin_files.col_id": "ID",
+  "admin_files.col_ingested": "Ingested",
+  "admin_files.col_local_filename": "local_filename",
+  "admin_files.col_missing_paths": "Missing paths",
+  "admin_files.col_modified": "Modified",
+  "admin_files.col_name": "Name",
+  "admin_files.col_original_file_path": "original_file_path",
+  "admin_files.col_original_filename": "Original Filename",
+  "admin_files.col_path_relative": "Path (relative to workdir)",
+  "admin_files.col_processed_file_path": "processed_file_path",
+  "admin_files.col_size": "Size",
+  "admin_files.delta_detected_detail": "Found {orphan_count} orphan file(s) on disk with no DB record, and {ghost_count} DB record(s) with missing files on disk.",
+  "admin_files.delta_detected_title": "Delta detected.",
+  "admin_files.empty_database": "No file records found in the database.",
+  "admin_files.empty_directory": "This directory is empty.",
+  "admin_files.ghost_records_desc": "(in DB, file(s) missing on disk)",
+  "admin_files.ghost_records_heading": "Ghost records",
+  "admin_files.heading": "File Manager",
+  "admin_files.health_missing": "Missing",
+  "admin_files.health_ok": "OK",
+  "admin_files.legend_file_exists": "File exists on disk",
+  "admin_files.legend_file_missing": "File missing from disk",
+  "admin_files.legend_found_in_db": "Found in DB",
+  "admin_files.legend_not_in_db": "Not in DB (orphan)",
+  "admin_files.legend_path_not_set": "Path not set",
+  "admin_files.no_delta": "No delta found \u2014 filesystem and database are in sync.",
+  "admin_files.no_ghost_records": "No ghost records found.",
+  "admin_files.no_orphan_files": "No orphan files found.",
+  "admin_files.orphan_files_desc": "(on disk, no DB record)",
+  "admin_files.orphan_files_heading": "Orphan files",
+  "admin_files.page_title": "File Manager \u2013 Admin",
+  "admin_files.status_in_db": "In DB",
+  "admin_files.status_orphan": "Orphan",
+  "admin_files.tab_database": "Database Records",
+  "admin_files.tab_filesystem": "Filesystem",
+  "admin_files.tab_reconcile": "Reconcile",
   "admin_users.add_user_profile_btn": "Add User Profile",
   "admin_users.admin_only_badge": "Admin Only",
   "admin_users.btn_password": "Password",