[FrankBro]

Summary

A model's default VAE could not be chosen, or applied, when the model decodes with another base's VAE (MOSS-Image, FLUX.3, ERNIE-Image, Ideogram 4, Z-Image, Krea-2, Qwen-Image, Anima).

• The default-settings VAE picker listed only VAEs of the model's own base, so a MOSS-Image model saw no FLUX.2 VAE. It now uses the same backend compatibility rule Generate applies, passed in through the scheduler policy so the Model Manager still loads no Generation code at startup.
• A new project's first-run Generate settings ignored the model's default VAE. They now include it.

I've only manually tested this with MOSS image, but it should apply to other families.

QA Instructions

• pnpm test src/features/generation (1657 passed), pnpm run lint:tsc, pnpm run format:check, oxlint on the touched folders, and the architecture dependency policy test all pass.
• New unit test: a new project whose first model names a default VAE of another base starts with that VAE. It fails without the fix.
• Not run: the Chromium browser tests (including the new picker coverage in AccountModelsUiProvider.browser.test.tsx) and check:release; Chromium is not installed in the author's worktree. The picker was tested manually.
• Manual: open a MOSS-Image model's detail page, turn on the default VAE row, and pick a FLUX.2 VAE. Start a new project and confirm the VAE is applied.

Review

Self-reviewed. Remaining limits: the picker lists no VAEs while the capability rules are loading or if they fail to load. A new project applies a default VAE only when the model it starts with has one.

Checklist

• The PR has a short but descriptive title, suitable for a changelog
• Meaningful regression coverage added / updated where needed; obsolete tests/code removed
• Persisted-state and API changes include required migrations / compatibility validation
• Relevant performance/efficiency opportunities considered; material claims have evidence
• Material review findings resolved and relevant checks rerun
• Documentation added / updated (if applicable)
• Updated What's New copy (if doing a release after this PR)

🤖 Generated with Claude Code

[Pfannkuchensack]

Thanks for tracking this down, the MOSS/FLUX.2 VAE picker gap is real. #10263 covers both parts of this PR: the Model Manager VAE picker now uses Generate's VAE rule, and a new project's first model applies its default VAE (along with the new default components, which are also applied on model switch). Since both PRs touch the same five files, I'd rather not carry the change twice, so I'm closing this one in favour of #10263. Your report is credited there.