Stores surrounding text (~100 chars) at the reader's current position. Used as fallback for CFI resolution when converting between epubcfi and CREngine XPointer formats. Updates: - schema.sql: add context_text TEXT column, update stored procedure - queries.sql: add context_text to GetUniversalProgress and UpdateUniversalProgress queries - Regenerate sqlc Go code (models.go, querier.go, queries.sql.go)