sqlite: opts + README doc accuracy — the config surface is the watcher cadence + reader pool, durability settings are bootstrapped constants (aligning with review-004 item 9's lib-header correction)

alkstore-sqlite/README.md

@@ -10,11 +10,10 @@ let store = alkstore_sqlite::open("store.db", alkstore_sqlite::SqliteOpts::defau
 
 **Engine posture — single-host, file-backed.** Cross-process on one
 host is verified territory; a `.db` on network storage (NFS
-two-writers) is not a supportable deployment posture. Durability
+two-writers) is not a supportable deployment posture. `SqliteOpts`
-knobs, pool sizing, and the watcher cadence are engine-configuration
+carries the watcher cadence and the reader-pool size;
-concerns on `SqliteOpts` — `synchronous = NORMAL` is hardwired at
+`synchronous = NORMAL` is hardwired at connection bootstrap — there
-connection bootstrap; there is no consumer surface to raise the sync
+is no consumer surface to raise the sync level.
-level.
 
 See the [family README](https://git.alk.dev/alkdev/alkstore/blob/main/README.md)
 for the interface and the deployment matrix, and the

alkstore-sqlite/src/opts.rs

@@ -19,10 +19,11 @@ pub const DEFAULT_MAX_READERS: usize = 8;
 /// Construction options for the SQLite engine's
 /// [`open`](crate::open) constructor.
 ///
-/// Durability knobs, pool sizing, and the watcher cadence are
+/// The engine's configuration surface (the watcher cadence and the
-/// engine-configuration concerns — they never appear on the contract
+/// reader-pool size) — the durability settings (`synchronous = NORMAL`,
-/// surface (ADR-008 §6); deployment.md carries the documented tuning
+/// the busy timeout) are bootstrapped constants, not knobs, per
-/// facts.
+/// deployment.md's posture (ADR-008 §6); they never appear on the
+/// contract surface.
 #[derive(Debug, Clone)]
 pub struct SqliteOpts {
     /// The watcher's `PRAGMA data_version` poll cadence. `None` = the