Reduce Lists Memory usage, update CI (#17706)

* Convert alerts to a lazylist

* Convert fullscreens to lazylist

* Convert ckeys_allowed_itemspawn to a lazylist

* Convert camera lists to lazylists

* Get rid of an old unused footstep_sounds list

* Make flooring_cache a lazy list

* Fix flooring_blacklist, convert a bunch more flooring lists to lazylists

* Improve ci byond caching

.github/actions/setup_node/action.yml

@@ -0,0 +1,26 @@
+# This action is a wrapper around `actions/setup-node`, to use the version specified in
+# `dependencies.sh`.
+name: Setup Node
+description: Install Node using the version specified in `dependencies.sh`; additionally, restores the Yarn cache if one exists
+
+inputs:
+  restore-yarn-cache:
+    description: 'If `true`, restores the Yarn cache alongside installing node.'
+    required: false
+    type: boolean
+    default: false
+
+runs:
+  using: composite
+  steps:
+    - name: Configure Node version
+      shell: bash
+      run: |
+        source dependencies.sh
+        echo "NODE_VERSION_REQUIRED=$NODE_VERSION_LTS" >> $GITHUB_ENV
+    - name: Install Node
+      uses: actions/setup-node@v4
+      with:
+        node-version: ${{ env.NODE_VERSION_REQUIRED }}
+        cache: ${{ fromJSON(inputs.restore-yarn-cache) && 'yarn' || '' }}
+        cache-dependency-path: ${{ fromJSON(inputs.restore-yarn-cache) && 'tgui/yarn.lock' || '' }}