feat(tui): render structured network approval prompts in approval overlay (#11674)

### Description
#### Summary
Adds the TUI UX layer for structured network approvals

#### What changed
- Updated approval overlay to display network-specific approval context
(host/protocol).
- Added/updated TUI wiring so approval prompts show correct network
messaging.
- Added tests covering the new approval overlay behavior.

#### Why
Core orchestration can now request structured network approvals; this
ensures users see clear, contextual prompts in the TUI.

#### Notes
- UX behavior activates only when network approval context is present.

---------

Co-authored-by: Codex <199175422+chatgpt-codex-connector[bot]@users.noreply.github.com>

codex-rs/tui/src/bottom_pane/mod.rs

@@ -1006,6 +1006,7 @@ mod tests {
             id: "1".to_string(),
             command: vec!["echo".into(), "ok".into()],
             reason: None,
+            network_approval_context: None,
             proposed_execpolicy_amendment: None,
         }
     }