Fix terminal stream backpressure and split-pane input lag

[Jinwoo-H]

Summary

• add daemon stream backpressure handling so PTY data/exit events preserve order, bound memory, and recover active sessions after stream failure
• keep visible inactive split-pane output on the shared terminal output scheduler so noisy build/install panes cannot monopolize xterm writes while the active pane receives input
• chunk large PTY IPC batches so one noisy PTY cannot serialize megabytes into the renderer in one main-process turn
• add focused daemon/main/renderer coverage plus a headful Electron split-pane regression

Validation

• Reproduced current installed Orca lag with a noisy inactive split pane: focus/typing into active pane stalled for multiple seconds
• pnpm run test:e2e:headful -- terminal-output-scheduler.spec.ts
• pnpm vitest run --config config/vitest.config.ts src/main/daemon/daemon-stream-data-batcher.test.ts src/main/daemon/client.test.ts src/main/daemon/daemon-server.test.ts src/main/daemon/daemon-pty-adapter.test.ts src/main/ipc/pty.test.ts src/renderer/src/components/terminal-pane/pty-connection.test.ts src/renderer/src/lib/pane-manager/pane-terminal-output-scheduler.test.ts
• pnpm run typecheck
• pnpm exec oxlint src/main/daemon/daemon-stream-data-batcher.ts src/main/daemon/daemon-stream-data-batcher.test.ts src/main/daemon/daemon-server.ts src/main/daemon/daemon-server.test.ts src/main/daemon/client.ts src/main/daemon/client.test.ts src/main/daemon/daemon-pty-adapter.ts src/main/daemon/daemon-pty-adapter.test.ts src/main/ipc/pty.ts src/main/ipc/pty.test.ts src/renderer/src/components/terminal-pane/pty-connection.ts src/renderer/src/components/terminal-pane/pty-connection.test.ts tests/e2e/terminal-output-scheduler.spec.ts
• git diff --check

Note: local commands emit the existing Node engine warning because this shell is on Node v25.9.0 while the repo wants Node 24.

Made with Orca 🐋