Centralize SQLite connection configuration (#33938)

## What changed

- Add `SqliteConfig` as the shared entry point for read-write and read-only SQLite pools.
- Apply consistent WAL, synchronization, auto-vacuum, busy-timeout, logging, and pool-size settings to writable Codex databases.
- Route state runtime, audit, CLI, and test database connections through the shared configuration.

## Testing

- Run migration tests against temporary on-disk databases opened through `SqliteConfig`, including the concurrent-writer repair case.

GitOrigin-RevId: e3946b98bde04c47574532ac8b1a7bb2b03edd97

codex-rs/state/src/runtime/remote_control.rs

@@ -159,9 +159,7 @@ mod tests {
     use crate::migrations::STATE_MIGRATOR;
     use crate::state_db_path;
     use pretty_assertions::assert_eq;
-    use sqlx::SqlitePool;
     use sqlx::migrate::Migrator;
-    use sqlx::sqlite::SqliteConnectOptions;
     use std::borrow::Cow;
 
     #[tokio::test]
@@ -338,13 +336,10 @@ mod tests {
             table_name: STATE_MIGRATOR.table_name.clone(),
             create_schemas: STATE_MIGRATOR.create_schemas.clone(),
         };
-        let pool = SqlitePool::connect_with(
-            SqliteConnectOptions::new()
-                .filename(state_db_path(codex_home.as_path()))
-                .create_if_missing(true),
-        )
-        .await
-        .expect("open old state db");
+        let pool = crate::SqliteConfig::new_for_testing(codex_home.clone())
+            .open_read_write_pool(&state_db_path(codex_home.as_path()))
+            .await
+            .expect("open old state db");
         old_state_migrator
             .run(&pool)
             .await