feat: comprehensive debug logging across all controller modules

Add detailed [DEBUG] logging to every controller module when
logging.level is set to "debug". Each module with stateful debug
uses SetDebug(bool) wired from main.go. Covers stacks, backup,
cloudflare, integrations, system, monitor, settings, scheduler,
web handlers, storage, metrics, API, selfupdate, and assets.

Also includes the app export/import (.fab bundles) feature from
v0.32.0 and its debug page integration.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CHANGELOG.md

@@ -1,5 +1,55 @@
 ## Changelog
 
+### v0.32.1 — Comprehensive debug logging across all modules (2026-02-26)
+
+#### Added
+- **stacks/delete.go**: Debug logging for DeleteStack/RemoveStack with stack state, HDD mounts, compose output, path removal; GetStackHDDData/GetStackBackupData path scanning
+- **stacks/manager.go**: Debug logging for ScanStacks per-stack discovery, refreshStatusLocked container resolution, Start/Stop/Restart pre-operation state, MigrateEncryption progress, getCatalogTemplateSlugs count
+- **stacks/deploy.go**: Debug logging for UpdateStackConfig/UpdateOptionalConfig changed keys, InjectMissingFields per-stack checks, SaveAppConfig encryption counts, LoadAppConfig results
+- **stacks/healthprobe.go**: Debug logging for per-target interval calculations and target collection summary
+- **backup/restic.go**: `debug` field + `SetDebug()` method; debug logs for Snapshot/Prune/Check/ListSnapshots/LatestSnapshot/Stats/RestoreAppData with timing, sizes, and command details
+- **backup/restore_scan.go**: Debug logging for ScanDrivesForBackups drive/app scanning with per-drive availability and backup component summary
+- **backup/restore_app_linux.go**: Debug logging for RestoreAppFromBackup step timing, restoreUserData per-dir rsync, restoreDBDumps per-file copying
+- **backup/restore_drives_linux.go**: Debug logging for MountDrivesFromLayout device discovery, mount strategy selection, fstab checks
+- **cloudflare/geosync.go**: `debug` field + `SetDebug()` method; debug logs for Sync zone/ruleset resolution, existing/desired rule diffing, rule create/update/delete operations
+- **cloudflare/waf.go**: Debug logging for GetCustomRulesetID/GetRules/GetFelhomRules counts, CreateRule/UpdateRule expression snippets
+- **cloudflare/zone.go**: Debug logging for GetZoneID progressive domain lookup attempts
+- **integrations/manager.go**: `debug` field + `SetDebug()` method; debug logs for Toggle validation/timing, ListForProvider counts, buildApplyContext details, ReapplyConfigForTarget per-integration progress
+- **integrations/lifecycle.go**: Debug logging for OnStackStop/OnStackStart/OnStackRemove with integration counts, state checks, revoke/re-apply operations
+- **integrations/onlyoffice_filebrowser.go**: Debug logging for Apply/Revoke config path, JWT secret presence, office URL
+- **system/**: Package-level `DebugLogger` variable; debug logs for GetInfo timing/summary, readMemInfo/readDiskUsage/readLoadAvg/readTemperature raw values, CPU collector samples, GetDiskUsage/GetFSInfo/CheckBackupDestination/ProbeStoragePath/IsUSBDevice details
+- **monitor/pinger.go**: `debug` field + `SetDebug()` method; debug logs for Ping/Fail/Start with UUIDs, send URL/attempts/response status
+- **settings/settings.go**: `debug` field (json:"-") + `SetDebug()` method; debug logs for Load counts, save data size, AddStoragePath/RemoveStoragePath, SetDisconnected/SetDecommissioned, AddPendingEvent/DrainPendingEvents, SetGeoRestriction, SetIntegrationState, AutoDiscoverStoragePaths
+- **scheduler**: `debug` field + `SetDebug()` method; debug logs for job registration, execution timing, daily job wait calculations
+- **storage/**: Consistent `[DEBUG] [storage]` prefix; scan timing; drive migration debug logging
+- **metrics/logscanner**: Debug logging for per-container scan timing, error/warning counts
+- **api/router**: `debug` field + `SetDebug()` method; logs incoming API requests and handler entry points
+- **selfupdate**: Expanded debug coverage with `dbg()` helper for TriggerUpdate preconditions, performUpdate step transitions, docker pull timing
+- **assets/syncer**: Expanded debug coverage with `dbg()` helper for per-file hash comparison, download timing, manifest fetch details
+- **web/auth.go**: Debug logging for RequireAuth middleware decisions, login attempts (IP, success/fail), session creation/cleanup
+- **web/handlers.go**: Debug logging for deploy/restore/settings/storage handler entry points with key parameters
+- **web/handler_restore.go**: Debug logging for restore page, status polls, restore-all execution per-app timing
+- **web/storage_handlers.go**: Debug logging for all storage API operations (scan, init, migrate, disconnect, reconnect, attach, cleanup)
+- **web/server.go**: Debug logging for NewServer initialization, template loading, ServeHTTP request routing
+- **main.go**: Wire `SetDebug()` for settings, pinger, geoSync, integrationMgr, scheduler, apiRouter
+
+### v0.32.0 — App export/import (.fab bundles) (2026-02-26)
+
+#### Added
+- **App export**: Per-app export to `.fab` bundles containing config, database dump, and all user data (HDD bind mounts or Docker named volumes)
+- **App import**: Restore apps from `.fab` bundles — works for both existing and new apps (standalone import page)
+- **Password protection**: Optional AES-256-CTR + HMAC-SHA256 encryption with scrypt key derivation for exported bundles
+- **Pre-export estimation**: Size estimation with free space check before starting export
+- **Export UI**: New export page accessible from app info header with drive picker, password field, stop-app checkbox, and real-time progress tracking
+- **Import UI**: Standalone import page (`/import`) scans all registered storage drives for `.fab` files, shows manifest details, and handles encrypted bundles with password prompt
+- **FileBrowser link**: After export, link to open the exports directory in FileBrowser
+- **Bundle format**: `{appname}_{timestamp}.fab` — tar.gz internally with `manifest.json`, `config/`, `database/`, `data/` directories
+- **New package**: `internal/appexport/` — export/import engine with provider adapter pattern (same as backup.StackDataProvider)
+- **API endpoints**: `/api/export/estimate`, `/api/export/start`, `/api/export/status`, `/api/export/bundles`, `/api/export/manifest`, `/api/export/import`, `/api/export/import/status`
+
+#### Changed
+- **backup/appdata.go**: Exported `ParseComposeNamedVolumes` (was lowercase) for reuse by appexport package
+
 ### v0.31.7 — Infra backup retention + version picker (2026-02-26)
 
 #### Changed