feat(scrape): vision OCR of image-only doc pages (support matrices)

Some HPE pages carry information only inside an image. The Morpheus
release schedule / support-lifecycle matrix (sf000111242en_us) is the
case that surfaced this: the entire "which version ships when, when a
stream hits Maintenance/EOL" table is a JPEG, so html_to_md dropped
every value and retrieval could never answer "when does 8.x.x reach
end of life".

New scrape/vision.py (opt-in via VISION_OCR) transcribes qualifying
images with a local Ollama vision model and appends a labeled markdown
block to the page so the text is chunked, embedded and retrieved.

Model/prompt chosen against ground truth on the matrix (14x4 cells):
- qwen2.5vl:7b + a bare "transcribe the table" prompt: 55-56/56, ~18s,
  GPU-resident, and prompt-ROBUST (accurate without hand-tuning).
- gemma3:12b needs an exact "read row by row, keep cells aligned"
  prompt or it shifts a column by one row; qwen2.5vl:32b is no more
  accurate and 5x slower (CPU spill). Both documented in the code.
- Note: self-consistency (2 samples must agree) only catches RANDOM
  flakiness — a wrong read is stable across seeds — so every block also
  ships a "verify against the source image" caveat.

Reliability/cost:
- content-hash cache in corpus/.vision-cache/ (committed) — each unique
  image OCR'd once ever, shared across version bundles.
- VISION_MAX_NEW bounds NEW OCRs per run so the first pass can't balloon
  into hours; the cache fills incrementally. Deferred count is logged.
- every failure path degrades to the pre-vision behavior; never blocks
  the scrape.

Also:
- add the morpheus_release_schedule bundle (sf single-doc) + 2 eval
  golden queries for it.
- fetch_single_doc: title falls back to the bundle title (not docId)
  when a page has no <h1> (sf solution articles).
- Pillow in requirements-vision.txt (scrape-only; kept out of the
  server image), installed + VISION_* wired into refresh.yml.

Verified locally: matrix transcribes to the exact 14-row table; second
run is a cache hit (ocr=0).

Co-Authored-By: Claude Opus 4.8 <[email protected]>
Claude-Session: https://claude.ai/code/session_01LFowQzJu7k97QLCRDSAeh1

scrape/bundles.py

@@ -95,6 +95,13 @@ BUNDLES: list[BundleSpec] = [
     BundleSpec("morpheus_quickspecs",          "a50009231enw",    "HPE Morpheus Enterprise Software QuickSpecs",
                "v1", "QuickSpecs", "html-file",
                source_url="https://www.hpe.com/psnow/doc/a50009231enw"),
+    # Release schedule / support-lifecycle matrix. This `sf` solution article
+    # is a single page whose table (which version ships when; when a stream
+    # hits Maintenance/EOL) lives ENTIRELY inside a JPEG. Scraped as `single`;
+    # the matrix text comes from the VISION_OCR pass (see scrape/vision.py).
+    # version=None — it spans all major streams, not one release.
+    BundleSpec("morpheus_release_schedule",    "sf000111242en_us", "HPE Morpheus Software Release Schedule",
+               None, "Release Schedule", "single"),
 ]