feat(gui): copy and paste with ctrl+c and ctrl+v in the terminal

[nikox96]

Summary

In the desktop terminal on Windows and Linux, copying needed Ctrl+Shift+C or the webview's right-click menu. This makes the plain keys work, as in Windows Terminal:

• Ctrl+C with a selection copies it and clears the selection. With nothing selected it still sends ^C, so a second Ctrl+C interrupts.
• Ctrl+V pastes. xterm skips the key and the webview's native paste lands in xterm's textarea, the same path Ctrl+Shift+V already took. Bracketed paste and the 8 KB terminal_write chunking are unchanged, and no clipboard plugin or new capability is needed.
• A Terminal setting ("Copy and paste with Ctrl+C / Ctrl+V"), on by default, turns both off and sends ^C and ^V to the remote again, for vim's visual-block mode and readline's quoted-insert. It persists like the other UI prefs (tauri-plugin-store + localStorage mirror). The row is hidden on macOS.
• Ctrl+Shift+C and Ctrl+Shift+V work either way. macOS is unchanged (Cmd+C/V).
• WebKitGTK under a non-Latin layout (keyCode 0) gets no native paste, so a bare Ctrl+V there goes through the existing terminal_paste command, like Ctrl+Shift+V already does.

The TUI is untouched: there, copy and paste belong to the host terminal, whose paste already arrives as bracketed paste.

Changes

• ui/src/lib/screens/terminalInput.ts: isBareCopy / isBarePaste next to isCopyShortcut, sharing one chord matcher (same keydown, IME and non-Latin rules).
• ui/src/lib/screens/TerminalView.svelte: handle the bare chords in the custom key handler when the pref is on.
• ui/src/lib/stores/terminalClipboard.ts: the new pref, shaped like streamer.ts; hydrated in +layout.svelte.
• ui/src/lib/screens/Settings.svelte: the Terminal switch.
• CHANGELOG.md: entry under ## Unreleased.

Test plan

• npm run check: 0 errors, 0 warnings
• npm test: the new terminalInput and terminalClipboard suites pass. select.test.ts fails on Windows before and after this change (path separators), unrelated.
• npx playwright test e2e/terminal.spec.ts --workers=1: the new and updated clipboard tests pass. The existing "host-first … then close" test fails locally on main too, unrelated.
• Manual check with cargo tauri dev: select + Ctrl+C copies; Ctrl+C with no selection interrupts sleep; Ctrl+V pastes in bash and in vim; with the setting off, Ctrl+V enters visual-block in vim.

[timhartmann7]

Thanks for the PR, the code is clean. We're keeping plain Ctrl+C and Ctrl+V for the shell, since vim, nano, emacs and readline rely on them, and Ctrl+Shift+C/V (or Ctrl+Insert/Shift+Insert) already copy and paste, so I'm closing this one.

[danstis]

Thanks for the PR, the code is clean. We're keeping plain Ctrl+C and Ctrl+V for the shell, since vim, nano, emacs and readline rely on them, and Ctrl+Shift+C/V (or Ctrl+Insert/Shift+Insert) already copy and paste, so I'm closing this one.

@timhartmann7 If the code is clean, could this function be hidden behind an option that defaults to off?
In my case I normally end up going back to Windows terminal on windows due to the simple copy/paste nature of the terminal, so would love to see this, but understand that many people would not. If it was an option that could be enabled, I believe it would be the best of both worlds.