fix: duplicate/interleaved terminal text while typing on macOS

[ohernandezdev]

Summary

Three independent, stacking causes were producing duplicated/interleaved
lines while typing in the embedded terminal, macOS-only (never on Windows):

• Orphaned PTY reader thread: spawn_pty's reader only checked its
  session gen when tearing down (to skip emitting pty-exit for a
  superseded session), not on every pty-output emit. A webview reload
  reusing a session id left the orphaned reader still emitting into
  whatever tab now owns that id — now every emit checks gen and the
  orphan stops as soon as it's superseded.
• WKWebView inline "writing suggestions" (Safari/WebKit 18+, macOS
  Sequoia): silently re-emitted the whole line typed so far as a single
  onData chunk mid-typing, which the shell echoed back as a duplicate.
  Confirmed with a debug write_pty log capturing the exact bulk re-send.
  Fixed via writingsuggestions="false" on xterm.js's hidden input
  textarea (autocorrect="off" also set — a different WebKit feature,
  not sufficient on its own).
• WKWebView: dead-key cancellation duplicates the dead char and drops the next key xtermjs/xterm.js#5894: on dead-key keyboard layouts (Spanish
  included), WKWebView duplicates the dead-key char and drops the
  following key. No native upstream fix yet — ported the reporter's
  addon-based workaround (src/xtermDeadKeyAddon.ts), removable once
  xterm.js fixes it natively.

Also bumps the app version to 0.8.2.

Test plan

• cargo check / tauri build --debug and tauri build (release) both compile clean
• Reproduced the bug pre-fix with a debug write_pty/pty-output log,
  confirmed the bulk-resend mechanism
• Manual testing typing in plain zsh and inside Claude Code sessions,
  release build, no recurrence after the writing-suggestions fix
• Extended real-world daily use to confirm no regression

🤖 Generated with Claude Code