fix: replace python3 with py/jq throughout scripts and docs

Windows Store python3 stub returns exit 49 instead of running Python.
Replace with: py (Windows launcher) for actual Python code, jq for
simple JSON extraction. Reorder fallback loops to try py first.
Add Bash(py:*) to settings.local.json allowlist.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.claude/commands/syncro.md

@@ -36,7 +36,7 @@ BASE="https://computerguru.syncromsp.com/api/v1"
 
 If `vault.sh get-field` fails (yq not installed), fall back to:
 ```bash
-API_KEY=$(sops -d D:/vault/msp-tools/syncro.sops.yaml | python -c "import sys,yaml; print(yaml.safe_load(sys.stdin)['credentials']['credential'])")
+API_KEY=$(sops -d D:/vault/msp-tools/syncro.sops.yaml | py -c "import sys,yaml; print(yaml.safe_load(sys.stdin)['credentials']['credential'])")
 ```
 
 ### Endpoints reference