fix(ci): Stabilize nox sessions by explicitly targeting the session python

The `nox` sessions were failing in CUpdate because `uv sync` was not installing dependencies into the correct session-specific virtual environments. This was caused by `uv` ignoring the `VIRTUAL_ENV` set by `nox` and defaulting to a different environment.

This commit resolves the issue by:
1.  Adding `--python str(session.python)` to all `uv sync` calls in `noxfile.py`. This explicitly tells `uv` which python executable to use, forcing it to install dependencies into the correct isolated virtual environment for each session.
2.  Removing all `external=True` flags from the `uv sync` calls, as they are no longer needed and were part of the problem.
3.  Removing a redundant `session.install("pydoclint")` call, as the dependency is already handled by `uv sync`.

These changes ensure that `tests` and `mypy` sessions run reliably. The `pre-commit` session is now configured correctly, although it may still face issues in certain CUpdate environments with unusual PATH configurations.

Author: bosd

noxfile.py

@@ -123,13 +123,12 @@ def precommit(session: nox.Session) -> None:
         "uv",
         "sync",
         "--python",
-        session.python,
+        str(session.python),
         "--group",
         "dev",
         "--group",
         "lint",
     )
-    session.install("pydoclint")
     session.run("pre-commit", *args)
     if args and args[0] == "install":
         activate_virtualenv_in_precommit_hooks(session)
@@ -143,11 +142,12 @@ def mypy(session: nox.Session) -> None:
     session.run(
         "uv",
         "sync",
+        "--python",
+        str(session.python),
         "--group",
         "dev",
         "--group",
         "mypy",
-        external=True,
     )
 
     session.install("mypy")
@@ -166,11 +166,12 @@ def tests(session: nox.Session) -> None:
     session.run(
         "uv",
         "sync",
+        "--python",
+        str(session.python),
         "--group",
         "dev",
         "--group",
         "lint",
-        external=True,
     )
 
     session.install("pytest", "coverage", "pytest-mock")
@@ -221,11 +222,12 @@ def typeguard_tests(session: nox.Session) -> None:
     session.run(
         "uv",
         "sync",
+        "--python",
+        str(session.python),
         "--group",
         "dev",
         "--group",
         "typeguard",
-        external=True,
     )
 
     session.install("typeguard", "pytest", "pytest-mock")
@@ -245,11 +247,12 @@ def xdoctest(session: nox.Session) -> None:
     session.run(
         "uv",
         "sync",
+        "--python",
+        str(session.python),
         "--group",
         "dev",
         "--group",
         "xdoctest",
-        external=True,
     )
     session.install("xdoctest")
     session.install("-e", ".")
@@ -266,11 +269,12 @@ def docs_build(session: nox.Session) -> None:
     session.run(
         "uv",
         "sync",
+        "--python",
+        str(session.python),
         "--group",
         "dev",
         "--group",
         "docs",
-        external=True,
     )
     session.install(
         "sphinx",
@@ -296,9 +300,10 @@ def docs(session: nox.Session) -> None:
     session.run(
         "uv",
         "sync",
+        "--python",
+        str(session.python),
         "--group",
         "docs",
-        external=True,
         env={"UV_PROJECT_ENVIRONMENT": session.virtualenv.location},
     )