Add option to suppress terminal responses

[assimelha]

Summary

Adds an emitTerminalResponses terminal option that defaults to the current behavior. When enabled, terminal-generated query replies continue to flow through onData. When disabled, writes are still parsed and rendered, but parser-generated replies such as DSR responses are not emitted through the same onData stream as user keyboard input.

Why

Some embedders terminate terminal queries at the PTY boundary or server-side mux layer. In those integrations, renderer-generated replies can race with or duplicate server-side replies, and because they are emitted through onData, they are indistinguishable from user input to the PTY. This option lets those embedders keep onData user-input-only while preserving the existing default behavior for browser-managed PTY integrations.

Validation

• bun run typecheck
• bun run fmt
• bun run lint
• bun run build:wasm
• bun test lib/terminal.test.ts
• git diff --check