Voice dictation for KDE Wayland: record, transcribe, clean up, paste

Ctrl+Space starts and stops a recording. The audio goes to OpenAI for
transcription, a model on OpenRouter strips the fillers and restores
punctuation, and the result is copied and pasted into the focused window.

Only the Python standard library and PyQt6 — HTTP, multipart uploads and
WAV writing are all hand-rolled.

- pw-record captures raw 16 kHz mono PCM with a live level meter
- the corner indicator is drawn through XWayland, since a Wayland client
  cannot position its own window
- silence is caught before it costs an API call, relative to each
  recording's own noise floor, plus a filter for the stock phrases models
  invent when handed silence
- audio and video files can be transcribed too, optionally with [mm:ss]
  timestamps, chunked through ffmpeg for long inputs
- global shortcut installs as a KDE custom shortcut, with an evdev
  listener as a fallback until the session is restarted
- Turkish and English interface, following the system locale by default

paste.py

@@ -0,0 +1,90 @@
+"""Clipboard (wl-clipboard) and key injection (ydotool)."""
+
+import shutil
+import subprocess
+import time
+
+from i18n import t
+
+# Linux input event codes (linux/input-event-codes.h)
+KEYCODES = {
+    "ctrl": 29, "control": 29, "shift": 42, "alt": 56, "super": 125, "meta": 125,
+    "v": 47, "insert": 110, "enter": 28, "return": 28,
+}
+
+
+class PasteError(Exception):
+    pass
+
+
+def read_clipboard():
+    if not shutil.which("wl-paste"):
+        return None
+    try:
+        res = subprocess.run(["wl-paste", "--no-newline"], capture_output=True, timeout=5)
+    except (subprocess.SubprocessError, OSError):
+        return None
+    return res.stdout if res.returncode == 0 else None
+
+
+def _run_wl_copy(payload):
+    """wl-copy forks to keep owning the selection; leaving its pipes open makes
+    subprocess.run wait for EOF forever, hence DEVNULL."""
+    return subprocess.run(
+        ["wl-copy"],
+        input=payload,
+        stdout=subprocess.DEVNULL,
+        stderr=subprocess.DEVNULL,
+        timeout=10,
+    )
+
+
+def copy(text):
+    if not shutil.which("wl-copy"):
+        raise PasteError(t("wl-copy not found. Install wl-clipboard."))
+    try:
+        res = _run_wl_copy(text.encode("utf-8"))
+    except (subprocess.SubprocessError, OSError) as exc:
+        raise PasteError(t("Could not copy to clipboard: {error}", error=exc)) from exc
+    if res.returncode != 0:
+        raise PasteError(t("wl-copy exited with code {code}.", code=res.returncode))
+
+
+def copy_bytes(data):
+    if data is None or not shutil.which("wl-copy"):
+        return
+    try:
+        _run_wl_copy(data)
+    except (subprocess.SubprocessError, OSError):
+        pass
+
+
+def ydotool_ready():
+    return shutil.which("ydotool") is not None
+
+
+def press(shortcut="ctrl+v", delay=0.12):
+    """Press a key combination through ydotool, e.g. 'ctrl+v'."""
+    if not ydotool_ready():
+        raise PasteError(t("ydotool not found — cannot paste automatically."))
+
+    codes = []
+    for key in (k.strip().lower() for k in shortcut.split("+") if k.strip()):
+        code = KEYCODES.get(key)
+        if code is None:
+            raise PasteError(t("Unknown key: {key}", key=key))
+        codes.append(code)
+
+    seq = [f"{c}:1" for c in codes] + [f"{c}:0" for c in reversed(codes)]
+    time.sleep(delay)  # let the selection settle and focus come back
+    try:
+        res = subprocess.run(["ydotool", "key", *seq], capture_output=True,
+                             text=True, timeout=10)
+    except (subprocess.SubprocessError, OSError) as exc:
+        raise PasteError(t("Could not run ydotool: {error}", error=exc)) from exc
+    if res.returncode != 0:
+        raise PasteError(t(
+            "ydotool failed: {error}\nIs ydotoold running? "
+            "(systemctl --user status ydotool)",
+            error=res.stderr.strip() or "unknown error",
+        ))