test: standardize naming conventions to snake_case

- Rename demo_event_id → testing_event_id (more explicit)
- Rename demo_account_id → testing_account_id (matches convention)
- Rename demo_badge_id → event_badge_id (descriptive)
- Rename demo_template_id → event_badge_template_id (explicit)
- Update all test files for consistency (15 files)
- Enhance README with organized test data sections
- Update person IDs to match README test data
- No regression: 15 tests passing, 7 pre-existing failures unchanged

tests/coldstart_event_settings.test.ts

@@ -1,8 +1,8 @@
 import { test, expect } from '@playwright/test';
 import { ae_app_local_data_defaults } from './_helpers/ae_defaults';
-import { demo_event_id, demo_account_id } from './_helpers/env';
+import { testing_event_id, testing_account_id } from './_helpers/env';
 
-const demo_event = demo_event_id;
+const demo_event = testing_event_id;
 
 test.describe('Cold-start: Event Settings (IndexedDB empty)', () => {
   test.beforeEach(async ({ page }) => {
@@ -30,13 +30,13 @@ test.describe('Cold-start: Event Settings (IndexedDB empty)', () => {
           mod_abstracts_json: {},
           // Provide a test person id so components that expect an authenticated
           // user/person render deterministically in tests
-          person_id: 'test-person-1',
-          user: { id: 'test-person-1' },
+          person_id: 'HMQRNPIXQMK', // Per README test data
+          user: { id: 'HMQRNPIXQMK' }, // Per README test data
           mod: { ...defaults.mod, events: { ...defaults.mod.events, event_id: event_id } }
         };
         window.localStorage.setItem('ae_loc', JSON.stringify(testData));
       },
-      { defaults: ae_app_local_data_defaults, event_id: demo_event, account_id: demo_account_id }
+      { defaults: ae_app_local_data_defaults, event_id: demo_event, account_id: testing_account_id }
     );
 
     // Navigate to the application's origin so the page context is allowed