release: prepare Desktop 0.13.10

docs/architecture/runtime-storage.md

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+# Runtime Storage And Background Reads
+
+SQLite owns persisted task, event and conversation evidence. The desktop business
+connection is long-lived. WAL permits readers alongside a writer; synchronous SQL
+still blocks the thread that executes it. Memory caches are disposable derived data.
+
+Startup storage upgrades run in `assistant-storage-worker` before the business
+connection opens. Runtime readers must not invoke initialization, migrations or
+recovery. `SubagentProgressStorage` caches event encoding state, not task statistics.
+
+## Runtime Read Design
+
+Execution statistics use one lazily started worker with a read-only connection.
+The worker performs the existing evidence query inside a short read transaction.
+Main supplies the current reply lease IDs and receives only scalar summaries.
+There is no worker pool or duplicate persisted summary. The worker is terminated
+when its owning database closes; errors reject reads, without a synchronous Main
+fallback. In-memory test databases use the synchronous query because independent
+connections cannot access the same private in-memory database.
+
+Derived caches must specify scope, capacity, lifetime and invalidation. Statistics
+keep at most eight scopes for 30 seconds. SQLite `data_version` detects other
+connections' commits; `total_changes()` detects writes on the owning connection.
+Reads inside an existing transaction clear and bypass the cache, so rolled-back
+values cannot escape. Closing the connection clears its cache. Live leases bypass
+the cache because elapsed time changes without a database write.
+
+Read transactions end before replies are posted. Long-lived read transactions
+would prevent WAL checkpoints from reclaiming old pages. Each reader has its own
+SQLite page cache; adding workers increases memory usage and requires evidence of
+parallel query demand. New consumers should reuse the same lifecycle and read-only
+rules, without introducing a general query protocol before a second use case exists.
+
+## Renderer Scheduling
+
+Hidden task panels use React `Activity` to preserve state while scheduling hidden
+render work below visible updates. Panel factories run inside that boundary.
+Terminal and browser panels retain their existing mounted effects and sessions.
+Statistics refresh only when the task center and document are visible. Results
+must remain scoped and late responses from a previous selection must be discarded.
+
+The [task statistics design](../features/task-and-job/technical-design.md) owns the
+query contract and evidence rules. Tests and timings demonstrate only their fixture
+conditions; they do not establish a latency guarantee for arbitrary retained history.