raop: fix read-side deadlock in PatchedIceCastClient (#2849)

[dantidote]

fixes #2849

When miniaudio.stream_any's decoder init issues a read larger than (BUFFER_SIZE - position) while position is still inside the seekable headroom, PatchedIceCastClient.read deadlocks against its downloader thread:

• read() polls until len(buffer) >= num_bytes, where len(buffer) is size (post-position bytes).
• The downloader's _buffer.fits(BLOCK_SIZE) guard checks the raw buffer length, not size, so once raw is at BUFFER_SIZE it refuses to add even though size has room to grow with consumption.
• Reader waits for the buffer to grow; downloader cannot grow it until the reader consumes. Polling loop hits DEFAULT_TIMEOUT (10s) and miniaudio surfaces the resulting OperationTimeoutError as DecodeError('failed to init decoder', -1).

Small streams escape because the HTTP body completes within the 10s window: _stop_stream flips True and the loop's other exit fires.

Detect 'raw buffer cannot grow' in the polling loop and let self._buffer.get() return a short read. miniaudio's drmp3 handles short reads by re-calling; once subsequent reads advance position past HEADROOM_SIZE the buffer releases its headroom and becomes a normal sliding window, after which the downloader can refill.

Tests use pytest-httpserver to serve the existing static_3sec.ogg fixture (small, exercises the fast path) and a new audio_long.mp3 (~80 KiB silence, just over BUFFER_SIZE) to trigger the deadlock. On master the long test fails after ~10s with DecodeError(-1); with this fix both tests pass in under a second.

Also bump the miniaudio dev pin from 1.61 to 1.71 in requirements/requirements.txt. The deadlock fires on 1.71's decoder init call sequence (the new seek(0, END) plus extra round-trip leaves position at 2048 when the read(65536) fires); 1.61's init ends with seek(0, START) which resets position before the same read, hiding the bug. Real users pip install pyatv and resolve miniaudio>=1.45 to the newest available (1.71 today, and only 1.71 has Python 3.14 wheels), but the old dev pin meant pyatv's own CI didn't exercise the bug pattern users hit. Bumping aligns CI with what users actually run so the new regression test serves as a real guard.

[Quentame]

You can add "fixes #2849" in the description so it links the issue with the PR and will auto-close it when the PR got merged 😉

[postlund]

@dantidote Not really sure what is wrong here, can you take a look? I can merge once tests pass.

[dantidote]

I think not all OSes are doing the reverse dns lookup right for localhost. Hoping this fix gets past it!

[postlund]

I think not all OSes are doing the reverse dns lookup right for localhost. Hoping this fix gets past it!

I forgot, there's already a way to serve files via http in tests:

pyatv/tests/conftest.py

Line 190 in b277a4c

def data_webserver_fixture(httpserver: HTTPServer, files: typing.Sequence[str]):

Can you switch to rust instead, so as don't re-invent things?

[dantidote]

OK switched to data_webserver. The tests all passed on my run now: https://github.com/dantidote/pyatv/actions/runs/27881135812