feat(capture): dictation, personalities, 0.5.0

Ships the Capture release end to end. Global-hotkey dictation with
synthetic paste into the focused app on macOS and Windows, an on-screen
pill across recording / transcribing / refining, customizable push-to-
talk and toggle chords, and an accessibility-permission prompt scoped to
Settings → Captures with inline re-check feedback.

Voice profiles gain optional personalities that power compose / rewrite /
respond actions via a local Qwen3 LLM — shared with refinement, so there
is one local LLM in the app, not two.

Refinement hardened with deterministic Whisper-loop collapse before the
LLM sees the transcript, per-capture flag snapshots for re-runs, and a
ten-transcript evaluation harness across every bundled refinement size.

Version bump 0.4.5 → 0.5.0.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

backend/config.py

@@ -119,6 +119,13 @@ def get_generations_dir() -> Path:
     return path
 
 
+def get_captures_dir() -> Path:
+    """Get captures directory path."""
+    path = _data_dir / "captures"
+    path.mkdir(parents=True, exist_ok=True)
+    return path
+
+
 def get_cache_dir() -> Path:
     """Get cache directory path."""
     path = _data_dir / "cache"