Prefer RuntimeEvent read model for session reads

[likun666661]

Summary

• Make SessionManager.getMessages() and listTurns() prefer RuntimeEvent-projected session views when durable per-run runtime ledgers are usable.
• Route retry/regenerate turn lookup, user-message lookup, and branch copy through the same RuntimeEvent-primary read view.
• Expand RuntimeEvent read projection for assistant thinking, abort source metadata, and multi-run lineage.
• Keep external IPC/preload/gateway/renderer contracts unchanged: callers still receive StoredMessage[] and TurnRecord[].

Rive

• Workflow: wfrun_65d83dede37f4a8bb7af4375ab5fbb89
• Scheduler: sched_715dace105ce4c7399692dafcfa46ff4
• Final verdict: pass_with_risks

Fallback policy

RuntimeEvent reads fall back to legacy SessionStore for no runStore, no runs, active/non-terminal runs, missing/empty runtime ledgers, missing terminal RuntimeEvents, hard projection diagnostics, run-store read failures, or hard compatibility gaps.

MAKA_RUNTIME_READ_SOURCE=legacy forces legacy reads as an emergency rollback.

Known risks

• AgentRunStore.readRuntimeEvents() still skips corrupt RuntimeEvent JSONL lines silently, so semantic compatibility remains the current safety boundary until storage exposes corruption diagnostics.
• The runtime view sorts RuntimeEvents chronologically with deterministic tiebreakers; the initial contract mentioned listSessionRuns/per-run concatenation. Tests pass with the chronological policy, but this should stay visible in review.

Verification

• npm run build --workspace packages/core
• npm run typecheck --workspace packages/runtime
• npm run test --workspace packages/runtime -- --runInBand (427 tests, 0 failures)
• git diff --check
• Rive stress node also ran npm run test --workspaces --if-present successfully, including desktop 1399 tests / 0 failures.

[likun666661]

Follow-up risk cleanup is pushed in 6a27af44 Harden RuntimeEvent read cutover.

What changed:

• AgentRunStore.readRuntimeEvents() now rejects durable corrupt RuntimeEvent JSONL rows instead of silently shortening the canonical ledger. Unterminated partial tails are still ignored as incomplete writes.
• SessionManager.readSessionView() now treats runtime-ledger read failure as an explicit legacy fallback path and carries the read error in diagnostics.
• Multi-run RuntimeEvent read ordering is locked to session chronology by RuntimeEvent.ts, with stable run/ledger/id tiebreakers and a regression test.
• MAKA_RUNTIME_READ_SOURCE=legacy now has an explicit rollback test.

Verification:

• npm run test --workspace packages/storage -- --runInBand: 80 tests / 10 suites / 0 failures
• npm run test --workspace packages/runtime -- --runInBand: 430 tests / 86 suites / 0 failures
• npm run build --workspace packages/core: pass
• npm run typecheck --workspace packages/runtime: pass
• git diff --check: pass
• npm run test --workspaces --if-present: core 614, storage 80, runtime 430, desktop 1399, all 0 failures

Final verdict: pass.