[Team] Bound agent loops and resource consumption #56

Planning ID: TODO-K

Proposed issue / PR title: feat(tasks): bound Chief delegation depth and per-task work budgets.

Goal: a request cannot generate unbounded Chief ping-pong or specialist spawning.

Scope: per-task hop/delegation and concurrency limits, an execution/time or token budget appropriate to available telemetry, stop propagation and visible exhausted-budget state. Apply across Chiefs and internal specialists; restarting or retrying does not reset the budget. Owners can stop their execution without granting another owner broader control.

Out of scope: billing, monetary cost guarantees and optimization dashboards.

Dependencies: TODO-I (#54), TODO-J (#55); use the creation-policy decision from TODO-A (#46)/#16.

Code area: task accounting, delivery, groups and tree limits/integration.

Acceptance and tests: looping Chief requests and recursive specialist requests stop at the configured limits, preserve spent budget across recovery, and report why work stopped. Ordinary bounded delegation still succeeds; cancellation interrupts downstream owned work and reports remaining external requests accurately.

Plan update (2026-10-16, team mode via groups): No separate team-mode subsystem is needed; groups with per-Bot grants cover it, and this is step 4 of the ordered plan on #51 (after #55). Effort: M.

• Gives: hop, unread, round and tree limits (MAX_HOPS, ROOM_BOT_ROUNDS, tree maxDepth / maxChildren) are per message or per room and reset on user input; restart does not count them.
• Gap: no per-task accounting and no visible exhausted state.
• Per-task persisted budget: on every run() with a meta.taskId, update task.budget = {hops, deliveries, children, startedAt, tokens?}. It is persisted and recovery never resets it. Limits come from a constants block (TASK_MAX_DELIVERIES, TASK_MAX_MS; tokens only if usage.js rows can be keyed to the task).
• On exhaustion: transition to failed with why:'budget' and a reason, deny further tagged sends (verdict in ownerPolicy style) and cancel the owned Bot turns. Tree createChild charges the task's children. Cancel from the requester or owner propagates only to Bots that owner owns.
• Files: tasks.js, hooks.js, tools.js, plugins/tree/src/tree.js, constants.js.

Delivery

One focused implementation PR for this issue. This is planned work, not a claim of shipped multi-human support. Preserve the pristine upstream pin and generated patch/client boundaries. Keep team mode disabled until the documented authorization gates pass. Record exact tested head, executed checks, missing checks and independent review. No production credentials or live deployment are part of this issue.