feat: add brain context() recall to the Python SDK (v0.2.0)

[mishanefedov]

Summary

• Adds context() — the brain's primary recall API (GET /v1/brain/context) — to the Python SDK. Previously only search/write/get were wrapped, so callers had to drop to raw httpx for prompt-ready recall.\n- New ContextResponse/ContextHit types (snake_case with wire aliases, extra=allow for forward-compat).\n- Wired into sync + async DocumentsResource, the UnisonBrain/AsyncUnisonBrain convenience methods, and the raw wrappers; exported from the package.\n- Bumped to 0.2.0.\n\n## Test plan\n- [x] test_context added; full suite passes (61 tests)\n- [x] live-tested against a running brain: client.context("…") returns ContextResponse (weak_evidence, hits[].snippet, context_md, top_score) and abstains on weak queries

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Summary by cubic

Adds prompt-ready recall via context() to the Python SDK by wrapping GET /v1/brain/context across sync, async, and raw clients. Introduces typed responses and bumps unisonlabs to 0.2.0.

• New Features

  • context() available on UnisonBrain, AsyncUnisonBrain, DocumentsResource, and raw wrappers.
  • Supports k, mode, max_entities, path_prefix, include_bodies (mapped to API aliases).
  • New types: ContextResponse and ContextHit (snake_case fields with wire aliases, extra=allow).
  • Returns context_md, weak_evidence, hits, top_score, and entities; includes test coverage.

• Migration

  • Upgrade to unisonlabs 0.2.0 and call client.context("your query") instead of hand-rolling HTTP calls.

^{Written for commit fe32da8. Summary will update on new commits.}