feat: Replace the gulp UI toolchain with Vite

.github/workflows/ui.yml

@@ -14,7 +14,8 @@ jobs:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
       - uses: actions/setup-node@cdca7365b2dadb8aad0a33bc7601856ffabcc48e # v4.3.0
         with:
-          node-version: '16'
+          node-version: '24'
           cache: npm
       - run: npm ci
+      - run: npm run lint --workspace ui
       - run: npm run bundle --workspace ui

.nvmrc

@@ -0,0 +1 @@
+24

Makefile

@@ -40,7 +40,7 @@ build-prod: build-ui
 	node_modules/.bin/antora generate antora-playbook.yml --fetch $(ANTORAFLAGS)
 
 build-ui:
-	node_modules/.bin/gulp --cwd ui bundle
+	npm run bundle --workspace ui
 
 build-search-index:
 	npm run build-search-index

README.adoc

@@ -62,7 +62,7 @@ content:
 
 The design & layout lives in the `ui/` directory of this repository.
 
-`LIVERELOAD=true gulp` may be used to recreate the built documentation after each edit.
+To see UI changes rendered with real content, rebuild with `make build-truly-local`.
 
 == More useful links