fix(install): quote PYTHON_PATH and UV_CMD for paths with spaces on macOS (#10009)

Cherry-picked from PR #10019 by @PStarH.

On macOS, uv stores Python in ~/Library/Application Support/uv/...
which contains a space. Unquoted $PYTHON_PATH and $UV_CMD caused
word-splitting under set -e, silently aborting install.sh.

Quotes all variable expansions in check_python():
- "$PYTHON_PATH" in command invocations
- "$UV_CMD" in uv calls
- Outer quotes on $(...) assignments

Closes #10009

scripts/release.py

@@ -175,6 +175,7 @@ AUTHOR_MAP = {
     "1506751656@qq.com": "hqhq1025",
     "364939526@qq.com": "luyao618",
     "hgk324@gmail.com": "houziershi",
+    "176644217+PStarH@users.noreply.github.com": "PStarH",
     "906014227@qq.com": "bingo906",
     "aaronwong1999@icloud.com": "AaronWong1999",
     "agents@kylefrench.dev": "DeployFaith",