fix(quota): make a paused Goal an authoritative terminal decision (supersedes #2447) (#2755)

* feat(quota): accept --quota-compute 0 as a Goal-level hard pause

Allow quota_compute=0 through a non-negative validator (was rejected as
"must be greater than 0") so an owner can hard-pause a whole Goal, and keep
rejecting negatives. Clarify the CLI help for the pause semantics.

Co-authored-by: TRAE CLI <noreply@bytedance.com>

* fix(quota): make a paused Goal an authoritative terminal decision

A paused Goal (quota.compute<=0) is now a typed terminal decision evaluated
before the selector builds any capability, workspace, replan, monitor, or
inbox candidate. build_quota_should_run short-circuits into one canonical
paused contract: should_run=false, all delivery/repair permissions false,
DONT_NOTIFY, scheduler never run_now, no quota spend, and no lane left with a
contradicting must_attempt_work signal. This replaces the previous behavior
where a paused Goal could still be promoted into repair_bridge/run_now by a
downstream lane.

Co-authored-by: TRAE CLI <noreply@bytedance.com>

* test(quota): cover paused-Goal authority and document compute=0

Add acceptance and parametrized consistency tests proving a paused Goal
preempts capability-bridge repair, workspace repair, due-monitor, user-gate,
and empty-frontier lanes with one terminal skip and no contradicting execution
signal anywhere in the payload. Cover configure-goal accepting compute=0 and
rejecting negatives. Document compute=0 (Goal-level hard pause) versus a single
agent's monitor_only lane in the quota allocation reference.

Co-authored-by: TRAE CLI <noreply@bytedance.com>

* fix(quota): stop paused host automation

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Co-authored-by: TRAE CLI <noreply@bytedance.com>
Co-authored-by: huangrt01 <huangrt01@163.com>