docs: point to PIT policy; track audioFile(Path) hermeticity gap

Add a 'PIT Mutation Testing' pointer to the workspace policy in CLAUDE.md, noting
the test-compile invocation rule and that this repo's gate is 100% only with the
audio fixture. Add an open TODO item for the non-hermetic value.ContentPart.audioFile(Path)
PIT gap (4 NO_COVERAGE mutants, killable only by the fixture-gated AudioInputIntegrationTest)
and the hermetic fix (a temp-file unit test mirroring the imageFile(Path) tests).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017i6A5bMhgCSbiKibQhxwuz

Author: claude

CLAUDE.md

@@ -1097,6 +1097,14 @@ See [`../workspace/policies/lombok-config.md`](../workspace/policies/lombok-conf
 
 See [`../workspace/policies/ci-test-diagnostics.md`](../workspace/policies/ci-test-diagnostics.md).
 
+## PIT Mutation Testing
+
+See [`../workspace/policies/pit-mutation-testing.md`](../workspace/policies/pit-mutation-testing.md).
+Run PIT with the lifecycle prefix — `mvn test-compile org.pitest:pitest-maven:mutationCoverage`
+(the bare goal fails with `NoSuchFileException: {argLine}`). Note: this repo's gate reaches 100%
+only with the audio fixture present; without it, `value.ContentPart.audioFile(Path)` is
+uncovered (98%) — see §4 of the policy.
+
 ## JPMS Module Descriptor
 
 This repo ships a `module-info.java` compiled in a separate `release 9` execution. Javadoc

TODO.md

@@ -13,6 +13,19 @@ cross-cutting initiative.
 
 ## Open — jllama-specific
 
+### PIT gate not hermetic — `value.ContentPart.audioFile(Path)` (open)
+
+The PIT mutation gate reaches 100% **only when the audio test fixture is present**. Without it the
+run is **98%**: 4 `NO_COVERAGE` mutants in `value.ContentPart.audioFile(Path)` (the null file-name
+guard, the `.wav`/`.mp3` extension dispatch, and `Files.readAllBytes`). The only test that exercises
+that method is `AudioInputIntegrationTest`, which is model-/fixture-gated and self-skips (`Assume`)
+when no audio clip is supplied (`net.ladenthin.llama.audio.input` — no committed default). So any
+environment lacking the clip (e.g. a network-restricted sandbox) reds the gate. Fix: add a hermetic
+temp-file unit test for `audioFile(Path)` — write a few bytes to a `@TempDir` `*.wav` / `*.mp3` and
+assert the format dispatch — mirroring the existing `imageFile(Path)` temp-file tests (PNG/JPG/GIF/
+WEBP), which already make the image path hermetic. See
+[`../workspace/policies/pit-mutation-testing.md`](../workspace/policies/pit-mutation-testing.md) §4.
+
 ### Code audit — pre-existing correctness / safety findings (RESOLVED — PRs #258 + #260)
 
 A multi-area audit (2026-06-20) of the **existing** codebase surfaced 18 correctness/safety findings,