## Why
Clients need a bounded view of realtime conversations that preserves the order of speech, agent work, and turn lifecycle events without loading the full thread history.
## What changed
- Persist realtime session boundaries, transcript segments, and promoted agent items in paginated thread rollouts.
- Add the experimental `thread/timeline/list` API to page ordinary items, realtime items, and turn boundaries in canonical rollout order. Include `activeRealtimeSessionAtPageStart` so each page can be rendered independently.
- Emit typed `thread/realtime/item/started`, `thread/realtime/item/transcript/delta`, and `thread/realtime/item/completed` notifications around durable realtime items.
- Keep the existing `thread/items/list` response and legacy thread history behavior unchanged.
## Testing
- Cover mixed timeline pagination, realtime-session state at page boundaries, rollout replay, subagent history prefixes, transcript streaming, steering, and promoted agent artifacts.
GitOrigin-RevId: faa2c420192d63e060e8fb32446e3c797422656e
## Why
Persisted item snapshots can be updated after their initial projection while retaining their creation order. Callers need a way to read those updates incrementally without replaying every item.
## What changed
- Track the rollout ordinal of each item's latest snapshot separately from its creation ordinal.
- Let thread-store callers filter items after an exclusive update watermark and sort pages by either creation or update ordinal.
- Keep existing app-server reads creation-ordered, reject incremental reads across forked lineages, and preserve compatibility with older writers.
## Testing
- Cover update-watermark filtering, pagination, sort directions, per-turn reads, cursor validation, forked lineages, migration compatibility, and refreshed item snapshots.
GitOrigin-RevId: d57de849abec27f788e9c384dbff073a0aca1053
## What changed
- Store the starting byte offset and terminal ordinal and byte offset for each turn projected into SQLite.
- Advance offsets across blank and rejected physical lines while leaving incomplete trailing lines for the next materialization pass.
- Stop later rollout records from changing a turn after it reaches a terminal state.
## Testing
- Cover active and completed turn positions, trailing partial lines, skipped invalid lines, subagent history prefixes, and records received after terminal state.
GitOrigin-RevId: a7da2f0b00c0bf47b841db874c79a0d495c18acd
## What changed
- Add the experimental `thread/searchOccurrences` app-server method for case-insensitive literal search across visible user messages and final assistant messages without replaying the thread.
- Return paginated snippets with UTF-16 match ranges and `thread/turns/list` cursors for navigating to each matching turn.
- Index persisted item types to efficiently select searchable messages from paginated thread history.
## Testing
- Add an app-server integration test covering pagination, steering messages, final-answer selection, Markdown normalization, and UTF-16 offsets.
GitOrigin-RevId: e80160e0f83eb4e5db8de862307085093bee362b
## What changed
- Project durable paginated rollout records into rebuildable SQLite tables for turns, items, and projection progress while keeping JSONL as the source of truth.
- Add cursor-based local reads for turn summaries and thread or per-turn items, including archived-thread and history-mode validation.
- Serialize writes, shutdown, and deletion per thread so projection updates cannot race cleanup, and remove projected rows when a thread is deleted.
- Preserve stable item ordering while updating repeated snapshots and expose structured turn error details.
## Testing
- Cover projection, snapshot updates, summary recovery, pagination, failure handling, shutdown flushing, legacy-mode rejection, and deletion races.
GitOrigin-RevId: 34533185ece7f1f5690004c7f12b0f1f34dc2640
## Why
Paginated thread history needs its own SQLite database to avoid adding lock
contention to the main state store.
## What changed
- Add the `thread_history_1.sqlite` path and migration scaffolding.
- Create tables and pagination indexes for projected turns and items, plus a
per-thread projection checkpoint.
- Register the database with runtime diagnostics, Bazel inputs, and database
telemetry.
GitOrigin-RevId: d194310835f1df2a2a29c7827d77ca37eabbd0a3
