Lint baseline: 47 react-hooks/refs warnings after eslint-plugin-react-hooks v7

[gizmax]

Context

PR #217 added .github/workflows/pr-tests.yml which runs ESLint. The freshly installed eslint-plugin-react-hooks v7 ships new rules (notably react-hooks/refs about accessing refs during render) that flag 47 pre-existing issues. ESLint is currently configured as advisory (continue-on-error) in the CI workflow.

Affected files

• src/pages/SettingsPage.tsx (multiple SaveButton dirty={isSectionDirty(...)} calls)
• src/components/runs/AiChatSidebar.tsx
• src/components/workflows/WorkflowBuilder.tsx
• Several others - see CI run https://github.com/gizmax/Sandcastle/actions/runs/25962232579 for the full list

Why the rule is correct

isSectionDirty() reads refs to compute its return value. Calling it inline in JSX accesses ref.current during render, which can produce stale UI when the ref changes without triggering re-render. React's docs recommend either:

1. Reading the ref into a state value in useEffect, or
2. Forcing a re-render via useState when the ref changes.

Effort

Each call site is a few lines. 47 sites total. Could be a single focused PR.

Acceptance

• npm run lint exits 0
• Remove continue-on-error from .github/workflows/pr-tests.yml ESLint step