Keep complete original histories accessible with indexed cursors

[Chris0Jeky]

The shared original-source picker now uses the last displayed source ordinal to load its next ten originals through the existing capture/ordinal index. It keeps long histories accessible without progressively deeper offset scans, includes ordinal zero, and preserves gaps between text sources. Owner, active-board, expected-revision and source-hash checks are unchanged.

Continues #2808. Stacked on source reliability PR2873. Legacy offset requests remain supported through1000; at the cap they expose no invalid next-offset link and provide nextAfterOrdinal for continued access. New clients begin afterOrdinal=-1. No schema migration, provider request or board mutation.

Verification

• Full backend:9184passed/34existing skips (Domain1639, Application4258, API3009, CLI243, Architecture28, Integration7). Final28ChatContextApiTests pass after the last legacy-offset boundary adjustment.
• Full frontend:6363passed/3existing skips across411files with two workers.14targeted picker/API tests, typecheck, productionbuild, scopedESLint, doclinks/governance and diffchecks pass.
• Original-source Chromium journey passed: twelve answer versions, second-page loading, original-first-answer selection, exact receipts across four experiences, permission recovery and375px accessibility. Isolated synthetic DB;5216/5316 stopped.
• Independent bounded Luna review found noHIGH/CRITICAL. Its MEDIUM invalid legacy continuation was corrected with the explicit1000boundary assertion above; final review disposition follows.

The first unrestricted-worker frontend run was stopped after an unchanged depth-token test reported a failure; it passed alone with two workers, and the complete bounded rerun passed. No claim that the initial run passed or that an unexplained failure is flaky. Full backend preceded only the final boundary condition; the complete affected API suite was rerun afterward. Logs and initial failures are retained under C:/Taskdeck-overhaul/evidence/source-history-cursors-*.

No production DB or primary checkout changed. Production-scale timing, physical devices, providers and restore acceptance remain unverified. OUTSTANDING_TASKS.md owner decisions remain unchanged.

[Chris0Jeky]

Independent bounded Luna review completed CLEAN for HIGH/CRITICAL. The final boundary pass confirms offset1000 now returns NextOffset=null plus usable NextAfterOrdinal1009, resolving the reported MEDIUM invalid-link finding. Root observed9184backend/6363frontend passes with34/3existing skips, final28API,14focusedfrontend, productionbuild and the real original-source browser journey. No production-scale timing/provider/device claim.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-10T02:09:42.657311Z	d5e5c6b	PR opened

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