* fix(codex): display renamed session titles
* fix(codex): resolve custom state db for titles
* refactor(codex): dedupe state-db resolution and harden title lookup
- Extract a shared `codex_state_db` module for `state_5.sqlite` path
resolution (config `sqlite_home` / `CODEX_SQLITE_HOME`), previously
copy-pasted verbatim between codex_history_migration and the codex
session provider. `state_5.sqlite` is now a single source of truth.
- Add `busy_timeout` to the read-only title query; without it a read
during a concurrent Codex write fails immediately (SQLITE_BUSY) and
renamed titles silently fall back to the first user message.
- Push the `title == first_user_message` comparison into the SQL WHERE
clause (NULL-safe, aligning with Codex's `distinct_thread_metadata_title`
semantics) and stop SELECTing `first_user_message`, which can hold
large values (openai/codex#29007) — the comparison belongs in SQL
anyway, so the column no longer needs to cross into Rust.
makoMakoGo