Fills small coverage gaps:
- shared_memory_test: SharedMemory create-or-open aliasing, move (steal + empty
the source, no double-free), reset, open-missing.
- wav_test: malformed input -- truncation, bad magic, missing data chunk,
over-long data size (clamps), odd-sized chunk (word-align skip), and a corrupt
~4 GB chunk_size. The reader gains an advance guard so that last case can't wrap
pos on a 32-bit size_t (x86) or spin the walk; it stops cleanly.
- tool_paths_test: deployed_artifact_path resolution -- next-to-exe, one-dir-up,
and the not-found fallback -- with real marker files.
- audio_ring_test: an overrun-at-the-seam case (write head near the end: a
wrapping push that fits vs. an over-capacity wrapping push dropped whole),
exercising the wrap split + overrun together, not just at offset 0.
The injector bitness check isn't added as a unit test: is_wow64_process is
file-local and the real WOW64 path needs a 32-bit target, so it stays
inspection-covered (and exercised by the x86 injection path).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>