The OpenAI-compatible vision client and the bounded prompt/output handling
for the analysis worker (no DB, fully unit-tested):
- analysis::prompt: terse system prompt carrying the JSON schema, the OCR
kind / content-warning vocabularies, and the output-size caps.
- analysis::vision: VisionClient (downscale via the new `image` dep →
base64 data-URL → chat/completions with an image_url part), plus pure
parse_chat_completion (fence/prose-tolerant) and sanitize (drop empty
OCR, truncate, clamp tags to 10 via the shared page-tag normalizer,
filter unknown warnings).
- config::AnalysisConfig extended with endpoint/model/api_key/timeouts/
max_tokens/max_image_dim/max_image_bytes + from_env.
- Deps: add `image` (jpeg/png/webp), reqwest `json` feature. Expose
api::page_tags::normalize_tag as pub(crate) for reuse.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
