Add external URL linting for markdown files

This commit integrates `remark-lint-no-dead-urls` into the project's
linting process, improving documentation quality by checking for dead
links.

Key changes:

- Add NPM command to verify external URLs in markdown files
- Include new command in the main lint script

Other supporting changes:

- Replace archive.ph link with Wayback Machine for better verification
- Update `remark-lint-no-dead-urls` to latest version (2.0.0)
- Update Browserslist DB to latest to avoid build errors

package.json

@@ -14,7 +14,7 @@
     "test:integration": "vitest run --dir tests/integration",
     "test:cy:run": "start-server-and-test \"vite build && vite preview --port 7070\" http://localhost:7070 \"cypress run --config baseUrl=http://localhost:7070\"",
     "test:cy:open": "start-server-and-test \"vite --port 7070 --mode production\" http://localhost:7070 \"cypress open --config baseUrl=http://localhost:7070\"",
-    "lint": "npm run lint:md && npm run lint:md:consistency && npm run lint:md:relative-urls && npm run lint:eslint && npm run lint:yaml && npm run lint:pylint",
+    "lint": "npm run lint:md && npm run lint:md:consistency && npm run lint:md:relative-urls && npm run lint:md:external-urls && npm run lint:eslint && npm run lint:yaml && npm run lint:pylint",
     "install-deps": "node scripts/npm-install.js",
     "icons:build": "node scripts/logo-update.js",
     "check:desktop": "vitest run --dir tests/checks/desktop-runtime-errors --environment node",
@@ -28,6 +28,7 @@
     "lint:md": "markdownlint **/*.md --ignore node_modules",
     "lint:md:consistency": "remark . --frail --use remark-preset-lint-consistent",
     "lint:md:relative-urls": "remark . --frail --use remark-validate-links",
+    "lint:md:external-urls": "remark . --frail --use remark-lint-no-dead-urls",
     "lint:yaml": "yamllint **/*.yaml --ignore=node_modules/**/*.yaml",
     "lint:pylint": "pylint **/*.py",
     "postinstall": "electron-builder install-app-deps",
@@ -71,7 +72,7 @@
     "markdownlint-cli": "^0.41.0",
     "postcss": "^8.4.39",
     "remark-cli": "^12.0.1",
-    "remark-lint-no-dead-urls": "^1.1.0",
+    "remark-lint-no-dead-urls": "^2.0.0",
     "remark-preset-lint-consistent": "^6.0.0",
     "remark-validate-links": "^13.0.1",
     "sass": "^1.77.8",