v0.4.0

Added

• commitbrief compress with three embedded prompts (light, balanced, aggressive). Atomic apply via temp + rename, backup at .commitbrief/backups/COMMITBRIEF-<timestamp>.md, refuses to apply when the result isn’t smaller. --out <path> writes elsewhere without touching the original.

Changed

• Verbose footer relabels Cost: to Saved: on local cache hits (no provider call was made; the figure is what would have been spent).
• Token line distinguishes provider prompt cache (provider cached: N) from CommitBrief’s local response cache (local cache hit).
• dry-run reports per-layer filter counts; list documents the three-layer filtering pipeline.
• Release pipeline goes live — Homebrew tap and Scoop bucket auto-publish.

Tests

Cumulative coverage rose from 64.7% → 77.8%. ~36 new tests across compress, render, CLI integration, provider streaming, and git dispatcher paths.