feat(policy): map --yolo to allowedTools wildcard policy

This PR maps the `--yolo` flag natively into a wildcard policy array
(`allowedTools: ["*"]`) and removes the concept of `ApprovalMode.YOLO` as a
distinct state in the application, fulfilling issue #11303.

This removes the hardcoded `ApprovalMode.YOLO` state and its associated
UI/bypasses. The `PolicyEngine` now evaluates YOLO purely via data-driven rules.

- Removes `ApprovalMode.YOLO`
- Removes UI toggle (`Ctrl+Y`) and indicators for YOLO
- Removes `yolo.toml`
- Updates A2A server and CLI config logic to translate YOLO into a wildcard tool
- Rewrites policy engine tests to evaluate the wildcard
- Enforces enterprise `disableYoloMode` and `secureModeEnabled` controls
  by actively preventing manual `--allowed-tools=*` bypasses.

Fixes #11303

packages/cli/src/ui/components/Help.tsx

@@ -153,12 +153,6 @@ export const Help: React.FC<Help> = ({ commands }) => (
       </Text>{' '}
       - Open input in external editor
     </Text>
-    <Text color={theme.text.primary}>
-      <Text bold color={theme.text.accent}>
-        {formatCommand(Command.TOGGLE_YOLO)}
-      </Text>{' '}
-      - Toggle YOLO mode
-    </Text>
     <Text color={theme.text.primary}>
       <Text bold color={theme.text.accent}>
         {formatCommand(Command.SUBMIT)}