Improves accessibility across the UI

Adds accessibility linting and strengthens keyboard and screen reader support with better roles, labels, focus handling, and semantic controls.

Documents intentional interaction exceptions, adds global focus and reduced-motion/high-contrast styles, and cleans up theme context usage to keep shared theme access simpler.

Author: IanSkelskey

eslint.config.js

@@ -2,12 +2,17 @@ import js from '@eslint/js';
 import globals from 'globals';
 import reactHooks from 'eslint-plugin-react-hooks';
 import reactRefresh from 'eslint-plugin-react-refresh';
+import jsxA11y from 'eslint-plugin-jsx-a11y';
 import tseslint from 'typescript-eslint';
 
 export default tseslint.config(
   { ignores: ['dist'] },
   {
-    extends: [js.configs.recommended, ...tseslint.configs.recommended],
+    extends: [
+      js.configs.recommended,
+      ...tseslint.configs.recommended,
+      jsxA11y.flatConfigs.recommended,
+    ],
     files: ['**/*.{ts,tsx}'],
     languageOptions: {
       ecmaVersion: 2020,