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/skills/1password/scripts/store_secret.sh

@@ -78,8 +78,8 @@ else
     "${FIELD}[password]=${VALUE}" \
     --format=json)
 
-  ITEM_ID=$(echo "$RESULT" | python3 -c "import sys,json; print(json.load(sys.stdin)['id'])")
-  VAULT_NAME=$(echo "$RESULT" | python3 -c "import sys,json; print(json.load(sys.stdin)['vault']['name'])")
+  ITEM_ID=$(echo "$RESULT" | jq -r '.id')
+  VAULT_NAME=$(echo "$RESULT" | jq -r '.vault.name')
 
   echo "✅ Created '${TITLE}' (ID: ${ITEM_ID})"
   echo ""