v0.1.37

Added

• okf diff --impact — dependency impact analysis traces changed deps → affected modules → downstream functions/classes. Uses ## Used By sections from existing bundles. Output: hierarchical tree or JSON (with --json). No new data required — used_by already populated by linker.
• MCP tool polish — get_concept (full detail by concept_id), find_callers (citators via ## Related link scanning), list_by_file (concepts by source file path). Enhanced lookup with detail=true param for full output (signature, params, source). Structured error handling for missing/invalid args. 6 new MCP protocol tests.
• GitHub Action — .github/workflows/okf-bundle.yml: auto-generates OKF bundle on push/PR to main. Caches previous bundle per branch, diffs with --compact + --impact, posts/updates single PR comment showing changes and dependency impact. Restores main branch cache for PR comparison.

Changed

• okf/diff.py refactored: diff_bundles() accepts optional pre-loaded concept lists to avoid double load when --impact is used.
• okf/mcp_server.py refactored: tool dispatch via _dispatch() with structured ToolError for validation.
• tests/test_diff.py: 11 total tests (6 new for impact analysis).
• tests/test_mcp.py: 11 total tests (6 new for MCP new tools + validation).

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