Replace the imperative loop that mixed mtime-tracking, transcript
reading, and validation with three clearly-scoped functions:
- compute_last_mtime: pure reduction over all m4as, returns max mtime.
- read_recordings: I/O loop that reads each transcript sidecar,
aborts on missing transcript (legacy "Nicht alle Aufnahmen sind
transkribiert" 400 body), silently skips blank ones.
- build_analysis_input: orchestrator that composes the above with
RFC3339 formatting.
Error bodies are preserved byte-for-byte. Replaces a one-pass loop
with two passes; n <= ~10 in practice - negligible.
Brummel
041f9015ca