Remove obsolete scripts and files, update site builder configurations

- Deleted the `import_plans.py`, `run_tests.py`, and `test_run.py` scripts as they are no longer needed.
- Updated the initial migration dependency in `0001_initial.py` to reflect recent changes in the `igny8_core_auth` app.
- Enhanced the implementation plan documentation to include new phases and updates on the site builder project.
- Updated the `vite.config.ts` and `package.json` to integrate testing configurations and dependencies for the site builder.

site-builder/vite.config.ts

@@ -20,6 +20,11 @@ export default defineConfig({
       '@shared': sharedComponentsPath,
     },
   },
+  test: {
+    environment: 'jsdom',
+    setupFiles: './src/setupTests.ts',
+    globals: true,
+  },
   server: {
     host: '0.0.0.0',
     port: 5175,