feat(loops): improve loop schedule display

[MattPua]

Problem

Loop detail views showed raw schedule/model values, which made common scheduled loops harder to scan.

Changes

• Format schedule triggers as readable times for common cron patterns.
• Show resolved default loop models when no model is configured.
• Add coverage for clock formatting and schedule display.

Screenshots: not included, display-only copy changes covered by tests.

How did you test this?

• pnpm --filter @posthog/shared test -- time.test.ts
• pnpm --filter @posthog/ui test -- loopDisplay.test.ts
• pnpm --filter @posthog/shared typecheck
• pnpm --filter @posthog/ui typecheck
• Full pre-commit pnpm typecheck failed in existing apps/web module resolution/type errors for @posthog/agent/* and @posthog/host-trpc/* imports.

Automatic notifications

• Publish to changelog?
• Alert Sales and Marketing teams?

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Created with PostHog Code

[trunk-io]

😎 Merged successfully - details.

[github-actions]

React Doctor found no issues in the changed files. 🎉

_{Reviewed by React Doctor for commit fa2c736.}

[greptile-apps]

Prompt To Fix All With AI

Fix the following 2 code review issues. Work through them one at a time, proposing concise fixes.

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### Issue 1 of 2
packages/ui/src/features/loops/hooks/useLoopRuns.ts:48
**Latest Run Mislabels History**

When a task is retried or run again, `task.latest_run` can refer to a newer execution than this loop-history entry. A failure or cancellation of that newer execution is then copied onto the older entry, including the wrong completion time and error message; reconciliation must identify the task run that actually backs this loop run.

### Issue 2 of 2
packages/ui/src/features/loops/hooks/useLoopRuns.ts:55-63
**Rejected Fetch Preserves Stale Status**

When `getTask` persistently returns 404 or 403, such as after a backing task is deleted or becomes inaccessible, this branch silently drops the result. The loop run remains `in_progress` on every poll even when the task already failed or was cancelled, preserving the stale state this reconciliation is intended to correct.

_{Reviews (1): Last reviewed commit: "fix: improve loop run and schedule displ..." | Re-trigger Greptile}

[github-actions]

Display-only formatting fix for loop schedule/model text (cron→readable time, resolved default model), backed by new unit tests; not risky territory. The unresolved Greptile findings concern useLoopRuns.ts, a file not touched by this diff — stale/inapplicable to the current change.

• Author wrote 0% of the modified lines and has 10 merged PRs in these paths (familiarity MODERATE).
• 👍 on the PR from greptile-apps[bot].

Gate mechanics and policy version

Gate		Result
prerequisites	✓	all clear
deny-list	✓	no deny categories matched
size	✓	76L, 5F substantive, 115L/7F incl. docs/generated/snapshots — within ceiling
tier	✓	T1-agent / T1c-medium (115L, 7F, single-area, fix)
stamphog 2.0.0b3		.stamphog/policy.yml @ 8e9165b · reviewed head fa2c736

[posthog]

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