refactor: drop milestone names + consolidate clients; loss-recovery & rumble fixes

Two bodies of work in one commit (the rename moved files the fixes also touched).

Naming/structure cleanup (pre-launch):
- Host modules m3.rs->punktfunk1.rs, m0.rs->spike.rs; CLI m3-host->punktfunk1-host,
  m0->spike; bare `punktfunk-host` now prints help. Types M3Options/M3Source->
  Punktfunk1Options/Punktfunk1Source.
- Clients consolidated out of crates/ into clients/: punktfunk-client-rs->
  clients/probe (crate punktfunk-probe), client-linux->clients/linux,
  client-windows->clients/windows, punktfunk-android->clients/android/native
  (crate punktfunk-client-android; kept [lib] name=punktfunk_android so the JNI
  contract is unchanged). crates/ now holds only core + host.
- Milestone codes M0-M4 purged from code/CLI/CLAUDE.md/README/docs/docs-site,
  kept only in docs/implementation-plan.md. docs/m2-plan.md->
  docs/gamestream-host-plan.md. CI/gradle/flatpak paths updated.

Client loss-recovery (video froze and never recovered after a brief drop):
- Export punktfunk_connection_frames_dropped through the C ABI (the core already
  tracked it for the client keyframe-recovery loop; it was never reachable from
  the ABI clients). Regenerated punktfunk_core.h.
- Apple (StreamPump + Stage2Pipeline) and Android (decode.rs) now poll
  frames_dropped and request a keyframe when it climbs -- the same loss-driven
  recovery Linux/Windows already had. Under infinite GOP the decoder silently
  conceals reference-missing frames, so the decode-error trigger rarely fires.

Apple rumble robustness (worked then went spotty -- DualSense + Xbox):
- Add CHHapticEngine stopped/reset handlers (rebuild on app background / audio
  interruption / server reset) and drop the permanent `broken` latch on a
  transient drive failure; latch only when the controller truly has no haptics.
- Surface swallowed SDL set_rumble errors on Linux/Windows + diagnostic logging.

Verified: cargo build/clippy/fmt --workspace, C-ABI harness, header drift.
Not runnable on this box (verify in CI): Gitea workflows, gradle/Android,
flatpak, Swift/decky.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/punktfunk-core/src/quic.rs

@@ -1,4 +1,4 @@
-//! `punktfunk/1` — the native control plane (M3), gated behind the `quic` feature.
+//! `punktfunk/1` — the native control plane, gated behind the `quic` feature.
 //!
 //! GameStream is punktfunk's compatibility layer; this is the start of its own protocol. A QUIC
 //! connection (quinn, tokio — control plane only, never the per-frame path) carries a
@@ -12,9 +12,9 @@
 //!
 //! after which both sides bring up a [`crate::session::Session`] over a plain
 //! [`UdpTransport`](crate::transport::udp) (native threads, no async) and the host streams.
-//! The Welcome carries everything the M1 core negotiates — FEC scheme (including GF(2¹⁶)
+//! The Welcome carries everything the core negotiates — FEC scheme (including GF(2¹⁶)
 //! Leopard, which GameStream can't express), shard sizing, crypto key/salt — so the data
-//! plane is exactly the hardened M1 `Session`.
+//! plane is exactly the hardened core `Session`.
 //!
 //! Transport security: the host presents a long-lived self-signed certificate
 //! ([`endpoint::server_with_identity`]) and the client pins its SHA-256 fingerprint