feat: terminal search/links/WebGL + SFTP symlink, hidden files and delete fixes

[qfxiongbinbin]

Summary

Terminal

• Cmd+F search bar (incremental highlight, Enter / Shift+Enter to jump, Esc to close) via @xterm/addon-search
• URLs in terminal output are clickable and open in the system browser (new open_external_url command, http/https only)
• WebGL renderer with silent fallback to the DOM renderer; scrollback raised to 5000 lines
• Shortcuts: Cmd+1-9 switch terminal tabs, Cmd+W close current tab, Cmd+K clear screen

SFTP

• Fix symlink parsing: ls -la lines with mode l... are now marked is_symlink and the arrow target suffix is stripped, so download/delete use the correct name (previously any symlink was broken)
• The placeholder path . is resolved to the real absolute remote directory via sftp pwd, so the path bar is readable and editable
• Show-hidden-files toggle for both panes (dotfiles hidden by default)
• Deleting a remote directory now works for non-empty directories (rm -rf over ssh; always behind the existing confirmation dialog)
• Double-click a remote file to download it, a local file to upload it

Test plan

• npm install, cargo check, npm run tauri dev
• Cmd+F finds text in scrollback; links open in browser; large output scrolls smoothly
• Cmd+1-9 / Cmd+K work; note Cmd+W may be intercepted by the native window menu
• SFTP: symlinks show a link icon with clean names; path bar shows an absolute path after selecting a host
• Hidden-files toggle filters dotfiles in both panes; deleting a non-empty remote directory succeeds after confirmation
• Double-click transfers work in both directions

🤖 Generated with Claude Code

https://claude.ai/code/session_015R3DVRqVdvkiD6YVchgcBv