fix(tui): Windows clipboard - use PowerShell directly for text paste

[MysticDevloper]

Problem

1. Admin terminal paste broken: On Windows Terminal running as Administrator, Ctrl+V paste does not work.
2. Text shrinking on copy: When copying text from the TUI output (Ctrl+Y or mouse selection), the text visually shrinks because clearSelection() triggers an immediate console redraw.

Root Cause

1. PowerShell Get-Clipboard can fail in elevated/admin terminal sessions due to session isolation.
2. renderer.clearSelection() is called synchronously after copy, causing the console to reflow and the selected text to visually collapse.

Fix

clipboard.ts

• Added Win32 API clipboard read via bun:ffi (user32.dll OpenClipboard/GetClipboardData/GlobalLock) that works in all terminal privilege levels (admin, elevated, UAC)
• Falls back to PowerShell Get-Clipboard, then clipboardy

selection.ts + app.tsx

• Added 150ms delay before clearSelection() after copy operations
• Prevents visual reflow/shrinking when the selection highlight is removed
• Applies to: selection copy, console copy (Ctrl+Y), and Escape dismiss

Changes

• packages/tui/src/clipboard.ts — Win32 API clipboard read for admin terminals
• packages/tui/src/util/selection.ts — Delay clearSelection by 150ms
• packages/tui/src/app.tsx — Delay console clearSelection by 150ms

Testing

Verified on Windows Terminal (normal + admin) — paste and copy both work without text shrinking.

[github-actions]

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[github-actions]

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[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Based on my search, here are related PRs that address similar clipboard/paste functionality (though no exact duplicates):

1. fix(tui): add plain text paste #34123 - fix(tui): add plain text paste - Directly related to text paste handling in the TUI
2. fix(tui): support clipboard image paste on Windows via FileDrop format #33507 - fix(tui): support clipboard image paste on Windows via FileDrop format - Windows-specific clipboard image paste support
3. feat(tui): insert absolute path for unsupported pastes and toast on failure #34307 - feat(tui): insert absolute path for unsupported pastes and toast on failure - Related paste functionality improvements
4. fix: preserve clipboard image paths for path-based MCP tools #36051 - fix: preserve clipboard image paths for path-based MCP tools - Clipboard path handling
5. fix(tui): support copying over ssh with set-clipboard on tmux config #30472 - fix(tui): support copying over ssh with set-clipboard on tmux config - Cross-platform clipboard support
6. fix(cli): Linux clipboard selection #32370 - fix(cli): Linux clipboard selection - Platform-specific clipboard handling

The most relevant is #34123 (plain text paste) as it directly addresses text paste behavior. You should review these PRs to ensure your fix doesn't conflict with or duplicate existing work, particularly around the bracketed paste event handling and PowerShell fallback strategy.

[github-actions]

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