perf: schedule agent timers from durable deadlines (#17876)

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https://entire.com/gh/paperclipai/-/trails/58/changes/paperclip/58
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## Thinking Path

> - Paperclip is the open source app people use to manage AI agents for
work.
> - Agent timers must start due work and preserve queue admission rules.
> - The server woke their scan on every heartbeat interval, even with no
eligible timer.
> - Idle scans keep the database and instance active.
> - This pull request derives the next deadline from saved policy and
work records.
> - Supported producer transactions notify the shared coordinator when
eligibility changes.
> - An idle timer worker stops scanning and resumes when real work or a
deadline requires it.

## Linked Issues or Issue Description

Refs #17863. This is slice 63 of the recurring-work migration and
follows the merged issue-monitor deadline PR.

Related: #16632 changes timer issue scope; #16881 changes live-run
eligibility. This PR preserves the current admission policy. Those
policy changes are separate work. A future time-sensitive predicate must
expose its next transition deadline.

**What existing behavior does this improve?**

Agent timer heartbeat scheduling in the server.

**Current behavior**

A recurring heartbeat wakes the timer scan even when companies are
paused, timers are disabled, or no actionable task exists.

**Proposed behavior**

Register the earliest eligible interval or positive daily-cap reset
deadline. Re-read on supported producer commits and startup. Leave no
recurring database scan when no timer obligation remains.

## What Changed

- Keep policy and deadline calculation in the heartbeat queue.
Scheduling retains company, reporting-chain, worktree, and CAS gates.
- Use the existing deadline coordinator. Remove only the timer wake from
the server heartbeat loop.
- Notify before existing transaction writes that change eligibility or
deadlines. Cover configuration, lifecycle, company budgets, task
ownership, recovery, conversations, accounting corrections, and
completion.
- Use the lifecycle status-change hook for saved hire rejection. Cover
checkout's second adoption transaction after an initial failed CAS.
- Preserve pending work through idle and maintenance drains. Check
cancellation between due agents. Reconstruct on restart.
- Document the supported writer model and producer inventory. Add no
schema, table, or provider branch.

## Verification

- **1,710 passing cases across 49 complete files**, no skips, on
accepted source `32db86c1974dcbf794f01a8c5e42024e2ad071fc`. Coverage
includes real timer policy/CAS/producers, monitor and shared deadline
consumers, native reconstruction, Slack lifecycle,
skills/settings/configuration, queue isolation and agent lifecycle.
- Database build, production server typechecking/build, module
boundaries, target migration order and Runner profile identity pass.
Twenty-nine fresh PostgreSQL 17 schemas plus per-file fixtures applied
all 412 journal entries through index 413; all selected source hashes
and temporary fixture imports were restored exactly.
- Four new deadline composition cases verify future/overdue timing,
minimum scan spacing and disarming. A controlled mutation dropping only
the inherited continuation option fails; the composed source passes with
identical assertions and timers.
- Normal parent reconciliation preserves task-drain expiry and both
deadline contracts. The final monitor-parent publication changes only
its audit, preserving every qualified runtime and selected test source.
- Historical failures and review corrections remain in [the timer
audit](doc/idle-agent-timers.md). No full local repository-suite, live
provider, measured suspend/wake, external-alarm or fleet-savings claim.
Final-head CI/security, exact-head Greptile 5/5 and actionable Ponytail
findings remain separate merge gates.

## Risks

- Process-local notifications cover supported service/API writers in one
server process. Direct SQL and independent replicas need an explicit
ingress contract. Startup reconstruction is not live cross-process
notification.
- Notifications can batch for up to the configured heartbeat interval.
Known deadlines retain their scheduler path; failed reconciliation
retains bounded retry.
- Enabled timers without an actionable-work requirement remain real
recurring obligations. Zero caps require policy changes; positive
reached caps use UTC midnight.
- The timer fixture substitutes adapter enqueue. Existing admission
tests also pass, but this is not deployed provider or sleep
qualification.
- Cloud does not gain legacy agent timer alarms in this PR. Existing
sleep-safety blockers remain. No database/host suspension or fleet
savings claim is made.
- Parent-stack CI and review must pass before merge. This PR does not
authorize merging its dependencies.

## Model Used

OpenAI Codex (GPT-6-based coding agent), using repository inspection,
normal Git merges, composition proofs, a controlled red/green regression
and complete PostgreSQL integration suites. No subagents were used in
this reconciliation.

## Checklist

- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have searched GitHub for duplicate or related PRs and linked
them above
- [x] I have either (a) linked existing issues with `Fixes: #` / `Closes
#` / `Refs #` OR (b) described the issue in-PR following the relevant
issue template
- [x] I have not referenced internal/instance-local Paperclip issues or
links (only public GitHub `#NNN` / `github.com/paperclipai/paperclip`
URLs)
- [x] My branch name describes the change (e.g. `docs/...`, `fix/...`)
and contains no internal Paperclip ticket id or instance-derived details
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [ ] All Paperclip CI gates are green
- [ ] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I will address all Greptile and reviewer comments before
requesting merge

---------

Co-authored-by: Paperclip <noreply@paperclip.ing>
Co-authored-by: Codex <noreply@openai.com>

server/src/modules/active-run-watchdog/adapters/postgres.ts

@@ -492,6 +492,7 @@ export function createPostgresWatchdogAdapter(db: Db): WatchdogRunReader & Watch
         ));
       const runningCount = Number(runningCountRow?.count ?? 0);
       const nextAgentStatus = runningCount > 0 ? "running" : "idle";
+      await notifyDeliveryWork(tx, DELIVERY_QUEUES.agentTimers);
       await tx
         .update(agents)
         .set({ status: nextAgentStatus, lastHeartbeatAt: new Date(), updatedAt: new Date() })

server/src/modules/agent-lifecycle/adapters/records.ts

@@ -100,6 +100,10 @@ export function agentRecords(db: Db, effects: LifecycleEffects) {
     },
 
     rejectPendingHire: async (id: string) => {
+      const [pending] = await db.select({ companyId: agents.companyId, status: agents.status }).from(agents)
+        .where(and(eq(agents.id, id), eq(agents.lifecycleState, "pending_approval"))).for("update");
+      if (!pending) return [];
+      await effects.beforeStatusChange(db, pending.companyId, id, pending.status, "terminated");
       const rows = await db.update(agents).set({ status: "terminated", lifecycleState: "rejected",
         lifecycleVersion: sql`${agents.lifecycleVersion} + 1`, lifecycleOperation: null,
         updatedAt: new Date() }).where(and(eq(agents.id, id), eq(agents.lifecycleState, "pending_approval"))).returning();