2026-08-27 Dashboard frontend Biome lint cleanup

Work Done

• Created chore/dashboard-frontend-biome-lint from origin/main in a separate worktree.
• Started from the app’s existing bun run lint:check result: 174 errors across 218 checked files.
• Applied safe mechanical fixes, then resolved accessibility, React key, non-null assertion, and document-preview security diagnostics without weakening workspace lint rules.
• Validated Biome (0 diagnostics), Nx typecheck, Nx build, module boundaries, and git diff --check.
• Confirmed that dashboard-frontend has no Nx test target or matching Bun tests; bun test reports No tests found!.
• Committed as 1ed2b659 and opened mono PR #355.

Lessons Learned: Pitfalls

• The dashboard SOP’s frontend lint baseline (~171) is close but stale; the current origin/main baseline was exactly 174 errors.
• The SOP says the frontend has no Nx typecheck target, but project.json now has one and bunx nx typecheck dashboard-frontend succeeds after building ui-components.
• Running typecheck before the shared ui-components build produces many misleading module-resolution errors.

Lessons Learned: Improvements

• Update the dashboard SOP with the current Nx targets and state clearly that the app still has no test target or test files.
• For future Biome cleanup, use the JSON reporter with --max-diagnostics=none to capture exact baseline counts and rule distribution before edits.
• Keep accessibility suppressions narrow and documented only where native HTML has no equivalent, such as keyboard-adjustable separators and interactive SVG chart marks.