chore: configure eslint rules and fix lint warnings

- Add eslint rules section downgrading strict react-hooks v7 rules to warn
- Remove unnecessary Boolean() wrappers across multiple pages
- Fix let→const for non-reassigned variable in AdminProgressPages
- Clean up stale eslint-disable-next-line comment and trailing whitespace
- Simplify setTimeout declaration in ManualPayPage

eslint.config.js

@@ -19,5 +19,17 @@ export default defineConfig([
       ecmaVersion: 2020,
       globals: globals.browser,
     },
+    rules: {
+      // ── New strict rules from react-hooks v7 — downgrade to warn ──
+      'react-hooks/set-state-in-effect': 'warn',
+      'react-hooks/exhaustive-deps': 'warn',
+      'react-hooks/preserve-manual-memoization': 'warn',
+      'react-hooks/immutability': 'warn',
+      'react-refresh/only-export-components': 'warn',
+
+      // ── Keep these as errors (real bugs / anti-patterns) ──
+      'react-hooks/static-components': 'error',
+      '@typescript-eslint/no-unused-expressions': 'error',
+    },
   },
 ])