Add classify, thumb_hash, perceptual_hash, crop_objects and preserve_hdr support

[11bit]

Closes #82
Closes #94

Upstream:

• imgproxy/imgproxy-docs@79b4eb3...451581c (Usage docs of imgproxy have been updated #82 — the five new options)
• imgproxy/imgproxy-docs@752e7bb...8d30510 (Usage docs of imgproxy have been updated #94 — crop_objects short keyword renamed co → c_obj)

Adds the five options that the Usage docs gained in those ranges.

Image info options (generateImageInfoUrl)

classify / cl

• top_k — required, integer >= 0. When greater than zero, imgproxy classifies the image and returns the top K classes with the highest confidence scores.
• class_names — optional; if given, imgproxy classifies only those classes.

generateImageInfoUrl(url, { classify: { top_k: 2, class_names: ["Bus", "Person"] } });
// -> /cl:2:Bus:Person/plain/...

thumb_hash / th — boolean; returns the image's ThumbHash.

perceptual_hash / phash / ph — boolean; returns the perceptual hash of the image.

generateImageInfoUrl(url, { thumb_hash: 1, perceptual_hash: true });
// -> /ph:t/th:t/plain/...

Processing options (generateUrl)

crop_objects / c_obj (PRO)

• scale_factor — required, number >= 0. 1.0 crops exactly to the detected objects, 1.2 adds 20% padding.
• class_names — optional; if omitted, imgproxy crops to all the detected objects.

preserve_hdr / ph — boolean; overrides IMGPROXY_PRESERVE_HDR.

generateUrl(url, { crop_objects: { scale_factor: 1.2, class_names: ["face"] }, preserve_hdr: 1 });
// -> /c_obj:1.2:face/ph:t/plain/...

On the co → c_obj rename

The crop_objects docs first landed with co as the short keyword, which collided with contrast — supporting both would have broken contrast (its build runs earlier and would throw on a CropObjects object) and made co unusable in the Options type. Upstream has since renamed the keyword to c_obj (#94), so this PR accepts crop_objects and c_obj and emits c_obj:. contrast keeps co and the two now coexist:

generateUrl(url, { contrast: 1.5, c_obj: { scale_factor: 2 } });
// -> /co:1.5/c_obj:2/plain/...

ph means perceptual_hash in image info URLs and preserve_hdr in processing URLs. That follows an established imgproxy convention — a is adjust or alpha, s is size or file size, f is output format or detected format — and this package already models s and f that way, so both keys are simply supported in their own namespace.

Out of scope in those compare ranges

docs/configuration/options.mdx, docs/features/*, docs/image_formats_support.mdx, docs/image_sources/*, docs/installation.mdx, docs/memory_usage_tweaks.mdx, docs/monitoring/* — server configuration and feature manuals, not URL options. docs/cache/**, versioned_docs/**, sidebars.ts, docusaurus.config.ts and versions.json — docs-site restructuring and version snapshots.

npm run lint, npm run check-types, npm run test -- --run (1237 tests) and npm run build all pass.

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https://claude.ai/code/session_01WQMVmChgR1GbXkCdrkFS4S