Refactor and improve external URL checks

- Move external URL checks to its own module under `tests/`. This
  separates them from integration test, addressing long runs and
  frequent failures that led to ignoring test results.
- Move `check-desktop-runtime-errors` to `tests/checks` to keep all
  test-related checks into one directory.
- Replace `ts-node` with `vite` for running
  `check-desktop-runtime-errors` to maintain a consistent execution
  environment across checks.
- Implement a timeout for each fetch call.
- Be nice to external sources, wait 5 seconds before sending another
  request to an URL under same domain. This solves rate-limiting issues.
- Instead of running test on every push/pull request, run them only
  weekly.
- Do not run tests on each commit/PR but only scheduled (weekly) to
  minimize noise.
- Fix URLs are not captured correctly inside backticks or parenthesis.

tests/checks/desktop-runtime-errors/check-desktop-runtime-errors/config.ts

@@ -0,0 +1,7 @@
+import { join } from 'path';
+
+export const DESKTOP_BUILD_COMMAND = 'npm run electron:prebuild && npm run electron:build -- --publish never';
+export const PROJECT_DIR = process.cwd();
+export const DESKTOP_DIST_PATH = join(PROJECT_DIR, 'dist');
+export const APP_EXECUTION_DURATION_IN_SECONDS = 60; // Long enough for CI runners
+export const SCREENSHOT_PATH = join(PROJECT_DIR, 'screenshot.png');