0.1.0 batch 6: bound and observe Reminder work

[suraciii]

Goal

Make Reminder scans and deliveries bounded, valid, and observable.

Scope

• Validate Reminder input before Store I/O.
• Acquire worker capacity before claim.
• List due rows in bounded cursor pages.
• Report actual delivery start time.
• Report scan, decode, claim, and callback failures with stable sources.
• Add the SQLite due-time index.

Acceptance

• Invalid rows are reported before claim.
• A large due set stays within fixed goroutine and memory limits.
• Two pollers deliver one claimed due time at most once.
• Scan and callback failures have different sources.
• make ci passes.

References

design/release-0.1.0.md
design/timers.md
design/observability.md

[suraciii]

Batch 6 work has started.

• Worktree: /home/szf/.herdr/worktrees/gor/release-0.1-batch6-reminders
• Branch: release-0.1-batch6-reminders
• Base: 991a3452a248e7ab3f5750a7a1032761d1fc47bf
• Baseline: make ci passed.

This batch will stop after implementation, review, full verification, and one local commit. It will not start Batch 7.

[suraciii]

Batch 6 local handoff is complete.

Worktree: /home/szf/.herdr/worktrees/gor/release-0.1-batch6-reminders
Branch: release-0.1-batch6-reminders
Commit: 0af3a47

Implemented:

• Reminder input validation before Store I/O.
• Bounded cursor pages and bounded Claim and Call workers.
• Dispatch validation before Claim.
• Actual delivery start in TickStatus.
• Separate scan, dispatch, claim, and Call failure sources.
• SQLite due-time index and readiness check.
• Memory, SQLite, simulation, and conformance updates.
• Batch 6 product, design, roadmap, and mutation records.

Proof:

• A 1,025-row due set stays within a 17-row page limit.
• Two pollers have one Claim winner.
• Applied Claim errors have the documented missed-delivery result.
• Abrupt shutdown does not wait for a Reminder method that ignores cancellation.
• Targeted mutations fail the tests that own the changed rules.
• make ci passed with exit code 0. It included format, constraints, vet, staticcheck, normal tests, all-package race tests, simulation, generator, and network tests.
• The worktree is clean.

Review found one roadmap mismatch and one shutdown concern. The roadmap is now current. A deterministic shutdown test proved the current mailbox cancellation boundary and prevents that concern from becoming a regression.

Batches 7 and 8 remain open. This commit was not pushed. No pull request was opened.

[suraciii]

Completed in the integrated candidate #116: Reminder validation, bounded cursor scans and workers, claim ordering, actual start reporting, stable failure sources, and the SQLite due index are covered by deterministic and resource tests. Exact master 0c41f9f644905183d7d4fd8f7efed24e4396bf0d passed local make ci and hosted run https://github.com/suraciii/gor/actions/runs/31504300130.