feat(clients): tiered stats overlay everywhere — Compact/Normal/Detailed on every platform

Ship the Android client's 3-tier stats-overlay semantics in every other client
(design/stats-unification.md vocabulary): Off → Compact (one line: fps · e2e ms ·
Mb/s + loss flag) → Normal (mode + e2e p50/p95 + loss counters) → Detailed
(decoder path, HDR tag, per-stage latency equation).

Apple: new StatsVerbosity in PunktfunkKit persisted under punktfunk.statsVerbosity
(migrates the legacy hudEnabled bool: explicit off → Off, else Normal). The
existing three-finger tap (TouchMouse, trackpad/pointer modes only — touch
passthrough untouched) now cycles the tiers instead of toggling, matching
Android; ⌃⌥⇧S (menu + captured-state monitor) cycles the same ladder. Tiered
StreamHUDView (compact glass pill / headline HUD / full equation HUD); the iOS
corner disconnect also shows in Compact (the pill carries no button). Tier
pickers on iOS, macOS, tvOS and the gamepad settings UI.

Session stack (Linux + Windows + Deck share punktfunk-session): shared
pf_client_core::trust::StatsVerbosity; Settings grows stats_verbosity with a
show_stats fallback, and writes keep the legacy bool in sync so pre-tier
binaries reading the same JSON agree on off vs on. Ctrl+Alt+Shift+S cycles the
tier and re-renders the OSD immediately from the last stats window; the stdout
stats: line always carries the full Detailed text so the shell status card and
scripts keep a stable shape; --stats bumps Off → Normal without demoting a
richer tier. Tier pickers in the GTK dialog, the WinUI settings page and the
console-UI settings row; shortcut copy updated (GTK shortcuts window, Windows
help, session README). The Windows legacy builtin path keeps its bool HUD.

Tests: tier migration/round-trip in trust.rs, tiered stats_text output in
pf-presenter.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

clients/apple/Sources/PunktfunkClient/Session/StreamCommands.swift

@@ -5,8 +5,9 @@
 // (the Linux client has its GTK Shortcuts window, Windows its start-of-stream banner). While
 // input is CAPTURED these key equivalents never reach the menu (the stream view swallows
 // keys); InputCapture's monitor detects the same combos there and performs the same actions —
-// the menu covers the released state and discoverability. The stats toggle just flips the
-// shared `hudEnabled` setting; ContentView reads the same @AppStorage and reacts.
+// the menu covers the released state and discoverability. The stats item cycles the shared
+// `statsVerbosity` tier (off → compact → normal → detailed → off); ContentView reads the same
+// @AppStorage and reacts.
 //
 // tvOS has no menu bar / hardware-keyboard command surface (disconnect there is the Siri
 // Remote's Menu button, handled by ContentView's `.onExitCommand`), so this whole file is
@@ -36,12 +37,16 @@ extension FocusedValues {
 
 struct StreamCommands: Commands {
     @FocusedValue(\.sessionFocus) private var session
-    @AppStorage(DefaultsKey.hudEnabled) private var hudEnabled = true
+    // The raw string so @AppStorage observes the shared key; the absent-key default runs the
+    // legacy-hudEnabled migration (same pattern as ContentView/SettingsView).
+    @AppStorage(DefaultsKey.statsVerbosity) private var statsVerbosityRaw
+        = StatsVerbosity.current.rawValue
 
     var body: some Commands {
         CommandMenu("Stream") {
-            Button(hudEnabled ? "Hide Statistics" : "Show Statistics") {
-                hudEnabled.toggle()
+            Button("Cycle Statistics") {
+                let current = StatsVerbosity(rawValue: statsVerbosityRaw) ?? .normal
+                statsVerbosityRaw = current.next().rawValue
             }
             .keyboardShortcut("s", modifiers: [.control, .option, .shift])
             // Reaches the key window's stream view via NotificationCenter — capture is view