feat: Enhance local command handling and introduce local intents

- Refactor `run_local_command` to manage subprocesses more effectively, ensuring child processes are terminated on timeout.
- Introduce `_terminate` function to handle process group termination and capture output.
- Implement `_command_output` to format command results with a character limit.
- Add local intent recognition in `intents.py` to handle commands like "stop", "go to sleep", and "come here" without server interaction.
- Normalize user input to match local intents while stripping filler words.
- Update tests to cover new local intent functionality and ensure proper command handling.
- Enhance speech processing to handle abbreviations and improve spoken output clarity.

tests/test_mic.py

@@ -112,3 +112,51 @@ def test_pcm_to_wav_bytes_round_trips_via_wave_module():
         assert wf.getframerate() == 16000
         frames = wf.readframes(wf.getnframes())
     assert np.frombuffer(frames, dtype=np.int16).tolist() == pcm.tolist()
+
+
+# ── flushing buffered audio ─────────────────────────────────────────────────
+
+class _BufferedStream:
+    """A stream with a backlog, like PortAudio's ring buffer after the reader
+    was blocked on a network call for a while."""
+
+    def __init__(self, available):
+        self.read_available = available
+        self.reads = []
+
+    def read(self, frames):
+        self.reads.append(frames)
+        self.read_available = max(0, self.read_available - frames)
+        return np.zeros((frames, 1), dtype=np.int16), False
+
+
+def test_flush_drops_exactly_what_was_buffered():
+    stream = _BufferedStream(4096)
+    assert mic.flush(stream) == 4096
+    assert stream.reads == [4096]
+    assert stream.read_available == 0
+
+
+def test_flush_is_bounded_so_it_cannot_chase_a_live_stream():
+    """A stream filling as fast as it drains must not spin forever."""
+    stream = _BufferedStream(10 ** 9)
+    dropped = mic.flush(stream, max_seconds=1.0, sample_rate=16000)
+    assert dropped == 16000
+
+
+def test_flush_is_a_noop_on_an_empty_or_fake_stream():
+    stream = _BufferedStream(0)
+    assert mic.flush(stream) == 0
+    assert stream.reads == []
+    assert mic.flush(_ScriptedStream([])) == 0   # no read_available at all
+    assert mic.flush(None) == 0
+
+
+def test_flush_swallows_a_device_error():
+    class _Broken:
+        read_available = 1024
+
+        def read(self, frames):
+            raise RuntimeError("device disappeared")
+
+    assert mic.flush(_Broken()) == 0