fix(ci): remove repo-level electron mirror defaults

fix(ui): restore preview download button hit area

chore(release): bump version to 2.8.0

fix(ui): remove deprecated router guard next callback

fix(test): align preview toolbar imports and evaluation fixtures

feat(image): refine reference style migration flow

fix(ui): harden safe image preview downloads

feat(image): streamline text2image reference replication flow

fix(image): stabilize cloudflare-backed reference flow

refactor(image): simplify reference prompt generation flow

fix(core): backfill builtin model api keys

fix(ui): persist cleared temporary variables state

refactor(image): rebuild reference prompt pipeline

feat(ui): redesign text2image reference dialog

docs(developer): sync prompt garden integration contract