Align repo config with global development standards

- Add missing tsconfig strictness flags (noUncheckedIndexedAccess,
  exactOptionalPropertyTypes, noImplicitOverride,
  noPropertyAccessFromIndexSignature) and fix all resulting type errors
- Replace ESLint/Prettier with oxlint 1.48.0 and oxfmt 0.33.0
- Pin all frontend and backend dependencies to exact versions
- Pin GitHub Actions to SHA hashes with persist-credentials: false
- Fix CI Python version mismatch (3.12 -> 3.14) and ruff target-version
- Add vitest 4.0.18 with jsdom environment for frontend testing
- Add ty 0.0.17 for Python type checking (non-blocking in CI)
- Add actionlint and zizmor CI job for workflow linting and security audit
- Add Dependabot config for npm, pip, and github-actions
- Update CLAUDE.md and pre-commit hooks to reflect new tooling
- Ignore Claude Code sandbox artifacts in gitignore

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/components/admin/FormModal.tsx

@@ -5,11 +5,11 @@ interface FormModalProps {
   onClose: () => void
   onSubmit: (e: FormEvent) => void
   children: ReactNode
-  submitLabel?: string
-  isSubmitting?: boolean
-  onDelete?: () => void
-  isDeleting?: boolean
-  headerExtra?: ReactNode
+  submitLabel?: string | undefined
+  isSubmitting?: boolean | undefined
+  onDelete?: (() => void) | undefined
+  isDeleting?: boolean | undefined
+  headerExtra?: ReactNode | undefined
 }
 
 export function FormModal({
@@ -55,11 +55,7 @@ export function FormModal({
                 onBlur={() => setConfirmingDelete(false)}
                 className="px-4 py-2 text-sm font-medium rounded-md text-red-600 dark:text-red-400 border border-red-300 dark:border-red-600 hover:bg-red-50 dark:hover:bg-red-900/20 disabled:opacity-50"
               >
-                {isDeleting
-                  ? 'Deleting...'
-                  : confirmingDelete
-                    ? 'Confirm?'
-                    : 'Delete'}
+                {isDeleting ? 'Deleting...' : confirmingDelete ? 'Confirm?' : 'Delete'}
               </button>
             )}
             <div className="flex-1" />