fix: comprehensive repo audit — 15 issues fixed

refactor: use API-reported supports_vision instead of hardcoded model names

feat(pipeline): IIIF-native Sprint 3 — in-memory image fetch for AI analysis

fix(sprint-f3): conformité spec — IIIF langue, ai_raw.json, prompts génériques

fix(sprint-f2): fiabilité — error handling, async I/O, pagination, cache, prompts

fix(sprint-f0): fondations — lazy imports, schémas conformes, pydantic-settings

feat: multi-provider dynamique — ajout Mistral/Pixtral, détection auto des providers

feat(sprint2-session-c): premier appel Google AI → master.json valide