[Audio] Generate recoverable waveform foundation

[yutthaphon]

Problem

The alpha requires timestamp-correct audio extraction and rebuildable waveform artifacts.

Change

Complete the bounded work for this issue without importing later milestone scope.

Behavior

Before: The required capability, decision, or evidence is incomplete.
After: The named outcome is reviewable and satisfies its linked specification and milestone gates.

Acceptance

• Dependencies and stable IDs are linked.
• Observable acceptance evidence is recorded.
• Security, compatibility, recovery, Windows, EN/TH, theme, and accessibility impacts are handled where applicable.
• No local Plan/ file is uploaded.

[yutthaphon]

Scope Clarification: Issue #30 Remains Open for Full Waveform Delivery

PR #46 merged Phase 00 foundations only:

• ✅ VID-IMPL-P00-002A (hostile preflight & fingerprint acceptance)
• ✅ VID-IMPL-P00-002B1 (contract bundle, fail-closed adapter)
• ✅ VID-IMPL-P00-002B2 C4 (records freeze, 41% dependency reduction)

Pending Delivery (Issue #30 remains OPEN):

• ⏳ VID-IMPL-P00-003A (waveform contract & cache foundation) — implementation authorized; secondary reviews required
• ⏳ VID-IMPL-P00-003B (real audio extraction) — awaits explicit decision gate (VID-DEC-003 extension)

Issue #30 Parent Scope: Complete recoverable waveform foundation (both 003A + 003B). Exit criteria not met until both sub-slices are delivered and verified. Issue remains open.

Decision Gate: Real extraction requires new explicit decision defining component, build, hash, licensing, formats, containment, and policy. Silent reuse prohibited.

[yutthaphon]

PR #47 Merged to Main

VID-IMPL-P00-003A implementation delivery completed via squash merge.

• Merge commit: 40f83167be286f0671a36f9523c02f6ecda736e5
• Files merged: 27/27 (all C9-accepted with verified bytes)
• Merge timestamp: 2026-08-02T13:04:19Z
• Source commits: fe5d96c (initial) + 071b7dd (C9 corrections)

This issue remains OPEN for VID-DEC-005/003B prerequisite evidence and authorization work; implementation for 003B phase is not yet authorized.

Current focus: VID-DEC-005 prerequisite evidence and review procedures.