Critique an Existing Architecture

Background: Native [platform] app, [SwiftUI / Compose]. Here's my
current architecture—structure, layers, and how data flows:
[describe it, or paste key files: a view, its view model, a repository]

Use case: Pretend you're a skeptical senior mobile architect reviewing
this before a big feature push. Tell me what will hurt us as the app
grows.

Implementation details: Look specifically for:
- Layer violations (UI reaching into data, business logic in views)
- God objects, massive view models, or singletons everywhere
- Tight coupling that will block testing or platform parity
- State that lives in too many places or flows in multiple directions
- Things that are over-engineered for the app's actual size

Deliverable: A prioritized list of issues (highest risk first). For each:
why it's a problem, the concrete symptom it'll cause later, and a
specific refactor to fix it—with the smallest safe first step.