fix(tui): keep approval controls visible for long prompts (#1132)

[Aaronontheweb]

Summary

Fixes #1132. Long shell_execute approval prompts (cd with many path arguments, etc.) wrapped over many lines inside the Input panel and pushed both the selection list and the [Enter] Confirm status hint off-screen, leaving users unable to respond.

The fix renders a summary + a bounded body + hint + selection list. Ctrl+V toggles between collapsed (one-line truncated) and expanded (multi-line) body. All sizing scales with the terminal: body width, expanded body cap, Input panel cap, and status bar text are all derived from live IAnsiTerminal.Width/Height at each render, and the page subscribes to ResizeEvent to re-render on terminal resize.

• IAnsiTerminal is injected into ChatPage. The DynamicLayoutNode callback reads width/height every render.
• Expanded body cap = panelMax - (4 + optionCount) where panelMax = max(8, terminalHeight / 2). Adapts to the actual ApprovalOptions.Count so the 5-option production set (Once, This chat, Always here, Always anywhere, Deny) doesn't clip.
• Body width budget = terminalWidth - 4; narrow terminals get a proportionally shorter truncation.
• Status bar picks short/medium/full key-hint variants by width (full ≥100 cols, medium ≥70, terse below). Model ID is dropped below 80 cols.
• [PgUp/PgDn] Scroll hint is restored to the pending-interaction state — the design's stated escape hatch for >cap bodies.
• Wire-level DisplayText (ShellApprovalMatcher.FormatForDisplay, ToolAccessPolicy, SessionToolExecutionPipeline) is unchanged — non-TUI surfaces (headless -p, JSON-RPC, future channels) still see the full prompt.

What the new screen looks like

Collapsed (default) on a 120-col terminal:

╭─Input────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│Approval required for shell_execute.                                                                                  │
│cd /Users/kevin/code/compiler/Diagnostics.pn compiler/Symbol.pn compiler/Binder /private/var/… [Ctrl+V to view full]  │
│Select an option and press Enter.                                                                                     │
│1. Once                                                                                                               │
│2. This chat                                                                                                          │
│3. Deny                                                                                                               │
╰──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
[Up/Down] Select [Enter] Confirm [Ctrl+V] View full [PgUp/PgDn] Scroll [Ctrl+Q] Quit | Approval required | test-model

Expanded (after pressing Ctrl+V) — body now scales to the available panel height:

╭─Input────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│Approval required for shell_execute.                                                                                  │
│cd /Users/kevin/code/compiler/Diagnostics.pn compiler/Symbol.pn compiler/Binder                                       │
│/private/var/folders/pj/ncqg4f1s58l87j6n_9xvnz9m0000gn/T/tmp.aa                                                       │
│/private/var/folders/pj/ncqg4f1s58l87j6n_9xvnz9m0000gn/T/tmp.bb                                                       │
│/private/var/folders/pj/ncqg4f1s58l87j6n_9xvnz9m0000gn/T/tmp.cc                                                       │
│/private/var/folders/pj/ncqg4f1s58l87j6n_9xvnz9m0000gn/T/tmp.dd                                                       │
│/private/var/folders/pj/ncqg4f1s58l87j6n_9xvnz9m0000gn/T/tmp.ee SENTINEL_TAIL_MARKER Patterns: cd                     │
│Select an option and press Enter.                                                                                     │
│1. Once                                                                                                               │
│2. This chat                                                                                                          │
│3. Deny                                                                                                               │
╰──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
[Up/Down] Select [Enter] Confirm [Ctrl+V] Collapse [PgUp/PgDn] Scroll [Ctrl+Q] Quit | Approval required | test-model

The tail of the body (SENTINEL_TAIL_MARKER Patterns: cd) now renders inside the Input panel — earlier versions of this branch clipped it at a hardcoded 5-row cap.

Full ASCII captures committed under src/Netclaw.Cli.Tests/Tui/__snapshots__/chat-approval-{collapsed,expanded}.txt.

Tests

ChatPageTests exercises the fix headlessly via Termina's VirtualTerminal (same pattern as ApprovalsManagerPageTests):

• LongApprovalBody_KeepsControlsVisible — direct regression for UX: Long approval prompts hide choices #1132 at 120×40.
• CollapsedView_ShowsEllipsisAndCtrlVHint, CtrlV_TogglesFullBodyAndKeepsControlsVisible, NewInteraction_ResetsCollapsedState — toggle and state semantics.
• NarrowTerminal_PreservesCtrlVHint — 60-col terminal: Ctrl+V affordance must remain visible.
• FiveOptionApproval_AllOptionsVisibleWhenExpanded — the canonical production option set fits in expanded mode without clipping.
• SmallTerminal_PanelDoesNotEatChatHistory — 16-row terminal: the Input panel cap scales down so the chat history pane still renders.
• Resize_RerendersStatusBarAndBody — 120 → 50 col resize re-renders with the shortened status text.
• LongApprovalBody_RenderedFrameSnapshot — writes the ASCII frames above to __snapshots__/.

Test plan

• dotnet test src/Netclaw.Cli.Tests — 752/752 pass (9 ChatPage tests + 743 existing)
• dotnet slopwatch analyze — 0 issues
• ./scripts/Add-FileHeaders.ps1 -Verify — clean
• Manual verification: launch netclaw chat against a real provider; trigger a long approval; resize the terminal; confirm layout adapts and Ctrl+V works as shown above.

Marked draft

Per request, opening in draft so the rendering and scaling behavior can be reviewed before merging.

[Aaronontheweb]

Haven't had a chance to test this locally but best as I can tell from the ASCII output from Termina's VirtualInputSource it should be resolved.