[DO NOT MERGE] probe: whisper linux-arm64 source-build baseline

[ogad-tether]

No-op change to trigger the transcription-whispercpp source pipeline on unmodified main.

Purpose: qvac#3310's source-built whisper addon hits GGML_ASSERT(device) (no CPU backend modules load; ggml_vulkan: No devices found) on ubuntu-24.04-arm integration (failing job), while main's published @qvac/transcription-whispercpp@0.12.0 prebuilds pass the same job (baseline run). This PR discriminates: source build from unmodified main (pre-reorg registry whisper-cpp port, current ggml-speech + addon code) —

• fails the same way → regression is in current source inputs on main (ggml-speech pin / addon glue), predates the repo reorg
• passes → the reorg overlay is implicated and we debug it before merging the reorg stack

Closes after one CI cycle either way.

🤖 Generated with Claude Code

[github-actions]

Review Status

Current Status: ❌ PENDING
Approvals so far: none

Pending reviews: Needs 1 Management or Team Lead, and 1 more from Management, Team Lead, or Member.

[ogad-tether]

Verdict: reproduces on unmodified main — the repo reorg (#3310 / qvac-ext-lib-whisper.cpp#94 stack) is not the cause.

build	linux-arm64 integration
published @qvac/transcription-whispercpp@0.12.0 prebuilds (run)	✅ pass
source build, unmodified main, pre-reorg registry port (this PR, run)	❌ ggml_vulkan: No devices found → GGML_ASSERT(device) ggml-backend.cpp:595, exit 134
source build, reorged tree overlay (#3310 run)	❌ identical signature

So: current source builds of the whisper addon lose their CPU backend modules on linux-arm64 (Vulkan module loads, reports no devices; no CPU variant loads → empty device registry → assert). Regression is in main's source-build inputs (ggml-speech pin's arm64 CPU-variant tiers and/or whisper-addon backend-packaging glue — tts passed the same job from source, parakeet's native tests also ran fine on arm64). It went unnoticed because desktop integration is label-gated and the published prebuilds predate the change. Tracked separately; closing this probe.

🤖 Generated with Claude Code