v0.5.1: Phase 8e — two-pass NR, chain reorder, tuned defaults

Reorder 14-stage pipeline: gate and NR now run before gain rider so
noise is cleaned at natural signal level. Add NR Cleanup (Pass 2) as
a gentle stationary-mode second pass after the gain rider catches
residual noise the rider amplified. Pass 2 hardcodes guide_stem=None
to avoid reusing the original noise profile.

New chain: gate → NR → gain_rider → de_plosive → nr_cleanup →
dereverb → HPF → EQ → comp_peak → comp_body → de_esser →
soft_clipper → reverb → limiter.

Tuned defaults from real-world testing: all effects enabled, gain
rider max 4 dB, NR Cleanup Strong, HPF 120 Hz, EQ Clean Up,
de-esser 5 kHz / 12 dB, soft clipper 1.8, reverb on. Enhanced
preset updated to match.

232 tests pass (12 new).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Artemarius

CLAUDE.md

@@ -33,7 +33,7 @@ VocalForge/
 │   │   ├── __init__.py
 │   │   ├── engine.py           # Playback + recording streams (sounddevice)
 │   │   ├── alignment.py        # Cross-correlation alignment (constrained)
-│   │   ├── effects.py          # 13-stage vocal processing pipeline
+│   │   ├── effects.py          # 14-stage vocal processing pipeline
 │   │   ├── mixer.py            # LUFS normalization + mixing
 │   │   └── noise_reduction.py  # Spectral gating + high-pass filter
 │   ├── separation/
@@ -102,7 +102,8 @@ Development follows PROJECT.md phases. Each phase is self-contained:
 - **Phase 8a:** Noise gate + de-reverb + preset system + UX improvements [DONE]
 - **Phase 8b:** Parametric EQ + compressor + NR mode selection (v0.3.1) [DONE]
 - **Phase 8c:** De-esser + reverb — completes 9-stage pipeline [DONE]
-- **Phase 8d:** Gain rider, de-plosive, serial compression, soft clipper — 13-stage pipeline [v0.5.0]
+- **Phase 8d:** Gain rider, de-plosive, serial compression, soft clipper — 13-stage pipeline [v0.5.0] [DONE]
+- **Phase 8e:** Two-pass NR, chain reorder — 14-stage pipeline [v0.5.1]
 - **Phase 11:** Settings persistence, drag-and-drop, error handling [v0.6.0]
 - **Phase 12:** Testing, PyInstaller exe, README screenshots [v0.7.0]
 - **Phase 10:** Auto-tune research & prototyping [v0.8.0]