Daemon permission-response timeout default

Goal

Let daemon interactions that require a human response wait indefinitely by default. Operators that require a wall-clock cap continue to use the existing permissionResponseTimeoutMs option or qwen serve --permission-response-timeout-ms flag.

Current boundary

BridgeClient sends ordinary permissions and ACP tool calls marked with _meta.qwenInteractionKind = "user_question" through the same permission mediator. The mediator owns the single per-request timer, so the shared bridge option remains the correct configuration boundary.

Behavior

• When permissionResponseTimeoutMs is omitted or 0, neither ordinary permissions nor ask_user_question requests install a wall-clock timer.
• A positive permissionResponseTimeoutMs, including one supplied by the existing CLI flag, applies to both interaction kinds.
• No environment variable, wire field, or question-specific option is added.
• Voter cancellation, session cancellation, prompt cancellation, disconnect cleanup, idle reaping, daemon shutdown, and pending-interaction caps are unchanged.

Non-goals

This change does not alter permission policy, pending interaction snapshots, daemon restart restoration, or the optional prompt-wide deadline.

Verification

Focused bridge tests cover both interaction kinds with the default disabled timer and with an explicit finite timeout. Existing CLI tests cover option parsing and validation; package build and type checks cover the shared option wiring.