docs(music): README refinement — composition + voice + ethos coherence

- Add above-fold lead claim (6/6 exact metrics, 11/11 checks) as bold summary line before product description
- Add cross-lane portfolio orientation sentence (one of 17 independent domain codecs)
- Add Commercial Readiness table with STAGED verdict, explicit NOT CLAIMED comp benchmark row, always-in-beta prose
- Demote source citation from blockquote to plain source line (cleaner scan)
- Tighten no-comp-benchmark note to be declarative rather than apologetic

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

Author: Zer0pa-Architect-Prime

README.md

@@ -2,6 +2,10 @@
 
 [![License: SAL v7.0](https://img.shields.io/badge/license-SAL%20v7.0-e5e7eb?labelColor=111111)](LICENSE)
 
+**6/6 exact roundtrip metrics. 11/11 checks passing. Bounded symbolic-score codec with note-local expression refinement. No audio waveforms. No comp benchmarks.**
+
+`zpe-music` is part of the [Zer0pa](https://github.com/Zer0pa) portfolio of encoding products — one of 17 independent domain codecs, each with its own proof surface.
+
 ## What This Is
 
 `zpe-music` is a music encoding product for canonical symbolic score data, with a bounded note-local expression refinement carried on the same score note. It targets MusicXML pipelines that need auditable roundtrip recovery of score structure plus note-local `attack`, `release`, and `dynamics`-derived fields.
@@ -20,9 +24,19 @@ It does not do audio understanding. The public surface is canonical symbolic sco
 | REPEATED_NOTE_CASE (`repeated_note_case_exact_rate`) | 1.0 | `proofs/artifacts/music_release_metrics.json` | `tests/test_music_expression_authority_roundtrip.py::test_repeated_note_expression_roundtrip_exact` |
 | REQUIRED_CHECKS_PASSED | 11/11 in 3.39 s | `validation/results/release_verification.json` | `validation/run_release_verification.py` |
 
-All seven metrics measured on the bounded authority test corpus (11 synthetic/controlled MusicXML cases). These are test-corpus results on the authority path, not production-generality claims. No comp-benchmark baselines (MP3/AAC/Opus/MIDI/MusicGen) exist in this repo — this is a symbolic-score codec, not an audio codec.
+All seven metrics measured on the bounded authority test corpus (11 synthetic/controlled MusicXML cases). These are test-corpus results on the authority path, not production-generality claims. This is a symbolic-score codec — no audio codec comp benchmarks (MP3/AAC/Opus/MIDI/MusicGen) exist or apply.
+
+Source: `proofs/artifacts/music_release_metrics.json`, `validation/results/release_verification.json`
+
+## Commercial Readiness
 
-> Source: `proofs/artifacts/music_release_metrics.json`, `validation/results/release_verification.json`
+| Field | Value |
+|-------|-------|
+| Verdict | STAGED |
+| Scope | Bounded authority path on synthetic/controlled MusicXML corpus |
+| Comp benchmarks | NOT CLAIMED — symbolic-score codec; no audio codec baseline applies |
+| Production generality | Not claimed beyond authority corpus |
+| Always-in-beta | Useful now on the bounded path; improving continuously |
 
 ## What We Prove