Add afd-plugin adapter and knowledge routing

[zuiho-kai]

Summary

• add a human-reviewed afd_plugin adapter for vllm-project/afd-plugin
• add the smallest repo-specific knowledge/repos/afd-plugin slice and register it in the repo index
• generalize Direct MCP changed-file routing to use adapter-declared review_routes, while keeping unmatched paths visible
• add tests for adapter aliases, canonical AFD URL routing, knowledge scoping, and changed-file routing

Validation

• uv run --extra dev pytest test/test_adapters.py test/test_routing.py test/test_mcp.py::test_mcp_docs_support_afd_plugin_scope test/test_thin_mcp.py
• uv run --with ruff ruff check src\infermatrix_copilot\adapters\base.py src\infermatrix_copilot\thin_mcp_server.py test\test_adapters.py test\test_mcp.py test\test_routing.py test\test_thin_mcp.py
• uv run --extra dev python knowledge\tools\check_knowledge_tree.py
• uv run --extra dev python knowledge\tools\check_wiki_lint.py

Knowledge tree validation passed with 0 errors and 2 existing size warnings.

Sub-agent smoke

A sub-agent ran a read-only smoke against vllm-project/afd-plugin#197:

• routed owners: config-validation, connectors-distributed, workers-runners, tests
• routed doc: repos/afd-plugin/rules.md
• unmatched paths remained visible: AFD docs and recipe Markdown files
• conclusion: route smoke passed; unmatched paths are preserved with the "must not be treated as covered" policy

Notes

An earlier draft PR #43 was closed as superseded because it was opened from an existing branch and included unrelated branch history. This PR is from a clean branch based on main.