fix(nests): bump preroll to 200 ms + surface persistent decode failures

Two audit follow-ups for receive-path interop with kixelated/moq web
publishers (NestsUI v2's reference encoder):

1. ROOM_PLAYER_PREROLL_FRAMES 5 → 10 (≈100 ms → ≈200 ms). The web
   reference encoder uses `groupDuration: 100ms` (5 Opus frames per
   group) and stacks another 100–200 ms of jitter on top via the
   relay's outbound forward queue under residential network
   conditions. 100 ms of preroll reliably underran on web speakers,
   producing audible clicks between adjacent groups; 200 ms covers
   the observed envelope while keeping perceived join latency well
   below the wire latency a listener already sees.

2. Per-subscription consecutive Opus decode-error counter in
   NestViewModel.openSubscription. Single-frame decode errors are
   normal noise — Opus PLC papers over a single bad frame and the
   prior code silently swallowed them — but a structural mismatch
   (wrong wire format, missing legacy-container varint strip,
   codec/channel-count mismatch, corrupted Opus) fails *every* frame
   in a row. The previous behaviour made exactly that class of bug
   invisible: no audio, no log, no UI signal.

   New logic increments a per-subscription AtomicLong on each
   DecoderError / EncoderError, resets on every successful onLevel
   tick. When the streak hits DECODE_ERROR_STREAK_LOG_THRESHOLD
   (50 frames ≈ 1 s of solid failures) we log ONE conspicuous warning
   tagged `NestRx` with the underlying throwable's stacktrace.
   Logged once per crossing (exact-equality, not modulus) so a stuck
   stream produces a single attention-grabbing line instead of a
   50 Hz flood.

   Picks the non-lambda Log.w overload deliberately so the throwable
   stacktrace survives — fires exactly once per stuck-stream streak,
   so the unconditional message-string build is fine.

Both changes are additive — no callers changed, no public API
touched. The stale `ROOM_PLAYER_PREROLL_FRAMES = 5` reference in
NestMoqLiteBroadcaster's framesPerGroup kdoc is updated to match.

https://claude.ai/code/session_014JfZJHSTvyYYWJbC9VbB47

nestsClient/src/commonMain/kotlin/com/vitorpamplona/nestsclient/audio/NestMoqLiteBroadcaster.kt

@@ -460,7 +460,7 @@ class NestMoqLiteBroadcaster(
          *     joining mid-broadcast has to wait until the next
          *     group boundary for the first frame. 50 frames = 1 s
          *     gap, which matches what the existing
-         *     `ROOM_PLAYER_PREROLL_FRAMES = 5` audio-buffer + the
+         *     `ROOM_PLAYER_PREROLL_FRAMES = 10` audio-buffer + the
          *     ~250 ms AudioTrack jitter buffer was already designed
          *     to mask. 100 frames (2 s) is past that.
          *   - QUIC stream-level reliability: each group is one uni