feat: download dirs, file transfer resume, Wails desktop app, PWA, CI

Daemon:
- Per-network download directories (-download-dir flag, set_download_dir IPC)
- File transfer resume after disconnection: .tmp.meta sidecars survive
  interruption; resume_offset in file-accept lets sender seek and continue
- set_download_dir IPC command; download_dir reported in state_snapshot

Protocol:
- PeerMessage.ResumeOffset (EXT-006) for file transfer resume
- IpcMessage.ShareNetworks json tag changed from "networks" to "network_ids"
  to fix duplicate json tag collision with Networks []NetworkInfo

Desktop app (cmd/app):
- Wails v2 shell embedding daemon logic directly (no subprocess)
- System tray on Linux/Windows via getlantern/systray; macOS hides to Dock
- OS notifications for message_received and file_complete via Wails events
- notray build tag for headless/CI builds without GTK tray headers
- build-app.sh: builds web frontend, copies dist, runs wails build

Web / PWA:
- manifest.json + Apple touch icon meta tags for mobile "Add to Home Screen"
- PNG icons (192px, 512px, 180px) generated from SVG
- Wails EventsOn("notify") hook in App.tsx for native OS notifications

CI:
- .gitea/workflows/build.yml: server binaries cross-compiled for 5 platforms,
  desktop app for Linux amd64, release artifacts published on v* tags

Docs:
- README: download dir, file transfer resume, desktop app, PWA, CI sections
- EXTENSIONS.md: EXT-004 daemon mode marked shipped; EXT-006 resume added
- FUTURE.md: roadmap updated

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

cmd/app/app.go

@@ -0,0 +1,130 @@
+package main
+
+import (
+	"context"
+	"log"
+	"os"
+	"path/filepath"
+
+	"github.com/wailsapp/wails/v2/pkg/runtime"
+
+	"github.com/waste-go/internal/crypto"
+	"github.com/waste-go/internal/ipc"
+	"github.com/waste-go/internal/netmgr"
+	"github.com/waste-go/internal/proto"
+)
+
+const wsPort = 17338
+
+// App is the Wails application backend.
+// It embeds the daemon directly — no subprocess needed.
+// The React frontend connects to the daemon's WebSocket IPC at ws://127.0.0.1:17338,
+// exactly as it does in browser-daemon mode.
+type App struct {
+	ctx context.Context
+	mgr *netmgr.Manager
+}
+
+func newApp() *App {
+	return &App{}
+}
+
+// startup is called when the Wails window is ready. It initialises the daemon,
+// starts the WebSocket IPC listener, sets up the system tray, and begins
+// forwarding message/file events to the webview as OS notifications.
+func (a *App) startup(ctx context.Context) {
+	a.ctx = ctx
+
+	dir := dataDir()
+	id, err := crypto.LoadOrCreate(dir, "")
+	if err != nil {
+		log.Printf("app: identity: %v", err)
+		runtime.MessageDialog(ctx, runtime.MessageDialogOptions{
+			Type:    runtime.ErrorDialog,
+			Title:   "waste — startup error",
+			Message: "Failed to load identity: " + err.Error(),
+		})
+		return
+	}
+	log.Printf("app: peer id: %s  alias: %s", id.PeerID().Short(), id.Alias)
+
+	a.mgr = netmgr.New(netmgr.Config{
+		MasterIdentity: id,
+		StoreDir:       dir,
+	})
+
+	// Forward daemon events to the webview and generate OS notifications.
+	go a.watchEvents()
+
+	// Start the WebSocket IPC server; the webview connects here (daemon mode).
+	go func() {
+		if err := ipc.RunWS(a.mgr, wsPort); err != nil {
+			log.Printf("app: IPC: %v", err)
+		}
+	}()
+
+	log.Printf("app: WebSocket IPC listening on 127.0.0.1:%d", wsPort)
+
+	// System tray (Linux/Windows; no-op on macOS — see tray_darwin.go).
+	a.startTray()
+}
+
+// shutdown is called when the Wails app exits.
+func (a *App) shutdown(ctx context.Context) {
+	if a.mgr != nil {
+		a.mgr.LeaveAll()
+	}
+}
+
+// watchEvents subscribes to all daemon events and emits OS notifications for
+// incoming messages and completed file transfers. The "notify" event is received
+// by the frontend via Wails EventsOn and displayed using the browser Notification API.
+func (a *App) watchEvents() {
+	if a.mgr == nil {
+		return
+	}
+	events := a.mgr.Subscribe()
+	defer a.mgr.Unsubscribe(events)
+
+	for evt := range events {
+		switch evt.Type {
+		case proto.EvtMessageReceived:
+			if evt.Message == nil {
+				continue
+			}
+			// Don't notify for messages sent by the local peer.
+			if a.mgr.MasterIdentity() != nil && evt.Message.From == a.mgr.MasterIdentity().PeerID() {
+				continue
+			}
+			runtime.EventsEmit(a.ctx, "notify", map[string]string{
+				"title": "waste — new message",
+				"body":  evt.Message.Text,
+			})
+
+		case proto.EvtFileComplete:
+			runtime.EventsEmit(a.ctx, "notify", map[string]string{
+				"title": "waste — file received",
+				"body":  filepath.Base(evt.Path),
+			})
+		}
+	}
+}
+
+// dataDir returns the OS-appropriate config directory for identity and stores.
+// macOS: ~/Library/Application Support/waste
+// Linux: ~/.config/waste
+// Windows: %APPDATA%\waste
+func dataDir() string {
+	base, err := os.UserConfigDir()
+	if err != nil {
+		if home, err := os.UserHomeDir(); err == nil {
+			return filepath.Join(home, ".waste")
+		}
+		return ".waste"
+	}
+	dir := filepath.Join(base, "waste")
+	if err := os.MkdirAll(dir, 0o700); err != nil {
+		log.Printf("app: mkdir %s: %v", dir, err)
+	}
+	return dir
+}

cmd/app/main.go

@@ -0,0 +1,66 @@
+// waste desktop app — Wails shell wrapping the daemon and React UI.
+// In dev mode the UI is served from the Vite dev server (http://localhost:5173).
+// In production the compiled frontend is embedded from frontend/dist/.
+package main
+
+import (
+	"embed"
+	"log"
+	"os"
+
+	"github.com/wailsapp/wails/v2"
+	"github.com/wailsapp/wails/v2/pkg/logger"
+	"github.com/wailsapp/wails/v2/pkg/options"
+	"github.com/wailsapp/wails/v2/pkg/options/assetserver"
+	"github.com/wailsapp/wails/v2/pkg/options/linux"
+	"github.com/wailsapp/wails/v2/pkg/options/mac"
+	"github.com/wailsapp/wails/v2/pkg/options/windows"
+)
+
+//go:embed all:frontend/dist
+var assets embed.FS
+
+func main() {
+	app := newApp()
+
+	logLevel := logger.INFO
+	if os.Getenv("WASTE_DEBUG") != "" {
+		logLevel = logger.DEBUG
+	}
+
+	err := wails.Run(&options.App{
+		Title:            "waste",
+		Width:            1200,
+		Height:           800,
+		MinWidth:         800,
+		MinHeight:        600,
+		DisableResize:    false,
+		Fullscreen:       false,
+		LogLevel:         logLevel,
+		LogLevelProduction: logger.ERROR,
+		AssetServer: &assetserver.Options{
+			Assets: assets,
+		},
+		OnStartup:  app.startup,
+		OnShutdown: app.shutdown,
+		Bind:       []interface{}{app},
+		// Hide the window instead of quitting when the close button is clicked.
+		// The user can quit via the app menu or by stopping the process.
+		HideWindowOnClose: true,
+		Mac: &mac.Options{
+			TitleBar: mac.TitleBarHiddenInset(),
+			About: &mac.AboutInfo{
+				Title:   "waste",
+				Message: "Decentralized friend-to-friend encrypted mesh networking.",
+			},
+		},
+		Windows: &windows.Options{
+			WebviewIsTransparent: false,
+			WindowIsTranslucent:  false,
+		},
+		Linux: &linux.Options{},
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+}

cmd/app/tray.go

@@ -0,0 +1,35 @@
+//go:build !darwin && !notray
+
+package main
+
+import (
+	_ "embed"
+
+	"github.com/getlantern/systray"
+	"github.com/wailsapp/wails/v2/pkg/runtime"
+)
+
+//go:embed appicon.png
+var trayIcon []byte
+
+func (a *App) startTray() {
+	go systray.Run(func() {
+		systray.SetIcon(trayIcon)
+		systray.SetTooltip("waste")
+
+		mShow := systray.AddMenuItem("Open waste", "Show the waste window")
+		systray.AddSeparator()
+		mQuit := systray.AddMenuItem("Quit", "Quit waste")
+
+		for {
+			select {
+			case <-mShow.ClickedCh:
+				runtime.WindowShow(a.ctx)
+			case <-mQuit.ClickedCh:
+				systray.Quit()
+				runtime.Quit(a.ctx)
+				return
+			}
+		}
+	}, func() {})
+}

cmd/app/tray_darwin.go

@@ -0,0 +1,14 @@
+//go:build darwin
+
+package main
+
+// On macOS, Cocoa requires the system tray to run on the main thread, which
+// Wails already owns. Full menu-bar tray integration is future work and would
+// require an NSStatusItem helper or a fork of systray that supports
+// RunWithExternalLoop on macOS.
+//
+// For now the app hides to the Dock when the window is closed (HideWindowOnClose)
+// and users can reopen it from the Dock or Cmd+Tab. The standard macOS Cmd+Q
+// binding quits cleanly via Wails.
+
+func (a *App) startTray() {}

cmd/app/tray_stub.go

@@ -0,0 +1,8 @@
+//go:build notray
+
+package main
+
+// Build with -tags notray to omit the system tray (no libayatana-appindicator3-dev needed).
+// Used for headless builds and CI environments that haven't installed the GTK tray headers.
+
+func (a *App) startTray() {}

cmd/app/wails.json

@@ -0,0 +1,12 @@
+{
+  "$schema": "https://wails.io/schemas/config.v2.json",
+  "name": "waste",
+  "outputfilename": "waste",
+  "frontend:install": "echo 'run: cd web && npm install'",
+  "frontend:build": "echo 'run: ./build-app.sh'",
+  "frontend:dev:watcher": "",
+  "frontend:dev:serverUrl": "http://localhost:5173",
+  "author": {
+    "name": "waste-go"
+  }
+}

cmd/daemon/main.go

@@ -21,6 +21,7 @@ func main() {
 	wsPort         := flag.Int("ws-port", 0, "port for WebSocket IPC (web UI); 0 = disabled")
 	anchorURL      := flag.String("anchor", "", "anchor WebSocket URL, e.g. ws://your-vps:17339/ws")
 	shareDir       := flag.String("share-dir", "", "directory to share with peers on the network")
+	downloadDir    := flag.String("download-dir", "", "base directory for received files; defaults to data-dir, split by network")
 	joinInvite     := flag.String("join", "", "waste: invite string — sets anchor URL and auto-joins the network on startup")
 	turnURL        := flag.String("turn-url", "", "TURN server URL, e.g. turn:your-vps:3478")
 	turnSecret     := flag.String("turn-secret", "", "shared secret for coturn use-auth-secret HMAC credential")
@@ -76,6 +77,7 @@ func main() {
 		StoreDir:       dir,
 		AnchorURL:      *anchorURL,
 		ShareDir:       expandHome(*shareDir),
+		DownloadDir:    expandHome(*downloadDir),
 		TurnURL:        *turnURL,
 		TurnSecret:     *turnSecret,
 	})