fix(legal): persist ordinary source apply progress

[zhengdaqi]

Summary

V24R9 closes the Legal Coverage observation gap found by the V24R8 Case 09
product run. Successful ordinary source merges now persist a deterministic
state-bound applied receipt, and only a verified current receipt can advance
convergence progress.

This is intentionally stacked on V24R8. It does not change Agent Core, O1,
validator acceptance, Progress Lease 8/2, Router, Memory, the model, the
corpus, immutable source repair, matrix handoffs, or authority closure.

Changes

• Persist source-merge-applied-<digest>.json after a successful ordinary
  source projection, bound to previous/current state, immutable proposal
  path/hash, and exact source IDs.
• Verify the receipt against the current validator state, immutable proposal
  bytes, exact reviewed source rows, safe paths, size bounds, and replay
  identity.
• Remove apply-ready preparation as progress authority; the verified receipt
  creates one semantic checkpoint and replay creates none.
• Add counterexamples for tampering, forged current-state claims, non-reviewed
  source status, one-time progress, and replay.
• Add the V24R9 protocol decision, reviewer-readable QA, complete logs, and an
  exact preserved Case 09 replay driver/result.

QA & Evidence

• Focused Legal Coverage and real Gateway: 45/45 passed. Covers receipt
  write/verify, tampering, forged state, immutable repair compatibility, real
  Gateway hook/tool behavior, Router/Memory off fixture, and O1 integrity.
  Artifact: .omo/evidence/20260727-v24r9-durable-source-apply-receipt/focused-legal-gateway.log.
• Complete repository suite: 308/308 passed with zero failures,
  cancellations, skips, or todos. Artifact:
  .omo/evidence/20260727-v24r9-durable-source-apply-receipt/full-suite.log.
• Preserved Case 09 replay: reconstructed exact pre-apply state
  74abe7..., applied 4 sources/23 facts to 4d3a3c..., and observed
  progressOrdinal 1 -> 2 -> 2. Artifact:
  .omo/evidence/20260727-v24r9-durable-source-apply-receipt/case09-replay-result.json.
• Static gates: all changed JavaScript parses and the complete base-to-head
  diff passes git diff --check.

Risks & Residuals

The complete production-model Case 09 has not yet run on V24R9. This PR is
code-, Gateway-, protocol-, and exact-failure-replay verified, but it must not
be merged or used to authorize V25/85 cases until a new immutable campaign
passes Gate 0, paired smoke, Case 05, and complete Case 09.

PilotDeck has no PR CI and no historical Cubic integration, so the committed
local evidence is the available code gate.