Frontend typechecking fails on 13 errors left after the SDK redesign. Restore Button loading indicators, correct the read-only WithAtom callback types and FileInfo import, use an ES2020-compatible controlled-input check, and remove unused sidebar routes and their route-generation exclusion.
Validation: frontend typecheck, production build, and Biome checks on all changed files pass. The build still reports its bundle-size warning. Broader frontend lint has 28 existing errors and 38 warnings outside these changes.
Related: https://linear.app/drexa/issue/DRE-39/restore-frontend-checks-and-verify-mvp-end-to-end