docs: add 2026-07-28 spec compliance driver document

New docs/plans/2026-07-28-spec-compliance.md — the driver and checklist for
2026-07-28 spec work. One requirements table per ToC section of the live
draft spec (489 rows: 235 compliant, 92 partial, 32 gap, 30 untested,
100 n/a), generated from a 15-section / 105-agent audit with every claimed
gap adversarially verified (73 confirmed: 1 P0, 14 P1, 58 P2; 17 refuted),
plus the gap register, e2e test-plan lanes, and deployment guidance
(Lambda/EC2, stateless 2026 posture).

The prior driver (2026-07-28-release-readiness-review.md) is banner-marked
superseded for open work and retained as the historical record.

Author: hortovanyi

docs/plans/2026-07-28-release-readiness-review.md

@@ -1,5 +1,10 @@
 # 2026-07-28 Release Readiness Review
 
+> **SUPERSEDED for open work (2026-06-11):** the active driver/checklist is now
+> [`2026-07-28-spec-compliance.md`](2026-07-28-spec-compliance.md) (per-ToC-section
+> requirement tables + verified gap register). This review remains the historical
+> record of the P0/P1 closure work.
+
 Branch: `feat/turul-mcp-protocol-2026-07-28`. Reviewed 2026-06-10 against the **live**
 MCP draft specification (https://modelcontextprotocol.io/specification/draft), the
 vendored pin (`crates/turul-mcp-protocol-2026-07-28/schema/draft-schema.ts`, sha256