Centralize SQLite connection configuration (#34808)

## What changed

- Add `SqliteConfig` to own the resolved SQLite home, runtime database paths,
  and shared read/write and read-only pool settings.
- Pass the configuration through state and local thread-store consumers,
  replacing standalone path helpers and duplicated connection setup.

GitOrigin-RevId: 7351b08da94b5c8b6c0bbe492f86aeeca0699d3c

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

@@ -157,7 +157,6 @@ mod tests {
     use super::StateRuntime;
     use super::test_support::unique_temp_dir;
     use crate::migrations::STATE_MIGRATOR;
-    use crate::state_db_path;
     use codex_utils_absolute_path::test_support::PathExt;
     use pretty_assertions::assert_eq;
     use sqlx::migrate::Migrator;
@@ -344,8 +343,9 @@ mod tests {
             table_name: STATE_MIGRATOR.table_name.clone(),
             create_schemas: STATE_MIGRATOR.create_schemas.clone(),
         };
-        let pool = crate::SqliteConfig::new_for_testing(codex_home.as_path().abs())
-            .open_read_write_pool(&state_db_path(codex_home.as_path()))
+        let sqlite = crate::SqliteConfig::new_for_testing(codex_home.as_path().abs());
+        let pool = sqlite
+            .open_read_write_pool(&sqlite.state_db_path())
             .await
             .expect("open old state db");
         old_state_migrator