Preserve original SQLite TEXT bytes and decode them using the database encoding in exported Python readers. Extend the real encoding matrix to leading FEFF and quoted column names.
45 focused tests, native public CLI and full export/helper parity checks, formatting and check:fast pass. Retains the original correction by ShuaixinHuang from #9074.
Fixes#9004.
Assisted-by: Reimu (gensokyo-skills:reimu-incident-triage)
