fix(ci): restore green CI — pin lint rules, repair two stale test assumptions

ast_rag/mcp/server.py

@@ -28,7 +28,11 @@
 from pathlib import Path
 from typing import Optional
 
-from mcp.server.fastmcp import FastMCP
+try:
+    # mcp >= 2.0 renamed FastMCP to MCPServer and moved it to mcp.server
+    from mcp.server import MCPServer as FastMCP
+except ImportError:  # pragma: no cover - mcp < 2.0
+    from mcp.server.fastmcp import FastMCP
 
 from ast_rag.models import ProjectConfig, StandardResult
 from ast_rag.repositories import create_driver, apply_schema

pyproject.toml

@@ -77,6 +77,13 @@ ast_rag = ["../schema/*.cql"]
 target-version = "py310"
 line-length = 100
 
+[tool.ruff.lint]
+# Pin the rule set explicitly. Without this ruff applies whatever its current
+# default happens to be, so a new ruff release changes what CI enforces with no
+# code change -- which is what took CI red on 2026-07-27 (321 of the 496 new
+# findings were UP045 alone). These four are the rules the tree is clean under.
+select = ["E4", "E7", "E9", "F"]
+
 [tool.mypy]
 python_version = "3.10"
 strict = false

tests/test_unsupported_language.py

@@ -46,7 +46,10 @@ def test_supported_extensions_covers_all_mapped(self) -> None:
     def test_supported_extensions_grouped_by_language(self) -> None:
         mapping = supported_extensions()
         assert mapping["java"] == [".java"]
-        assert mapping["typescript"] == [".ts", ".tsx"]
+        # cd75313 moved .tsx onto a dedicated TSX grammar and added .jsx to it,
+        # so .tsx is no longer grouped under "typescript".
+        assert mapping["typescript"] == [".ts"]
+        assert mapping["tsx"] == [".jsx", ".tsx"]
         assert ".cpp" in mapping["cpp"]
         assert ".h" in mapping["cpp"]