QVAC-23972 feat[api]: describe classification modelConfig fields

[lauripiisang]

🎯 What problem does this PR solve?

• The classification (ggml-classification) modelConfig fields carried only JSDoc comments, which don't reach the generated contract (contract/schema.json) — so qvac configure, the typed-client generators, and the Python generator had nothing to say about what any field means.

📝 How does it solve it?

• Adds .describe() to every classificationConfigSchema field: modelPath, topK, nativeLogger.
• Text promoted from the existing in-schema JSDoc; corroborated against @qvac/classification-ggml index.d.ts / README — no invented semantics.
• Regenerates contract/schema.json and the Python generated models.

Part of QVAC-23933.

🧪 How was it tested?

• bun run contract:export regenerated; contract:check, typecheck, lint, format, and full test:unit (incl. contract-export freshness) pass.
• packages/inference typecheck + lint pass.
• packages/sdk-python generate.py --check passes.

🔌 API Changes

Additive only — descriptions are now readable off the contract and typed clients:

classificationConfigSchema.shape.topK.description
// "Limit returned results to the top-K classes. Default: all classes."

[github-actions]

Review Status

Current Status: ❌ PENDING
Approvals so far: none

Pending reviews: Needs 1 Management or Team Lead, and 1 more from Management, Team Lead, or Member.

[github-actions]

License compliance — clean

No new dependency license findings in this PR.

Warn-only (shadow) mode — this check does not block merges yet.

Updated automatically by the canonical license compliance workflow.

NOTICE presence (advisory)

Missing NOTICE (advisory, does not block):

• ./.github/actions/release-merge-guard
• ./docs/website
• ./packages/ggml-coload-smoke
• ./packages/fabric/test/integration
• ./packages/inference-addon-cpp/mobile
• ./packages/sdk/e2e
• ./packages/llm-llamacpp/benchmarks/performance
• ./packages/llm-llamacpp/benchmarks/server
• ./packages/vla-ggml/sim/server
• ./packages/embed-llamacpp/benchmarks/performance
• ./packages/embed-llamacpp/benchmarks/server
• ./packages/asr-ggml/benchmarks/server