install-node: Upgrade Node.js to 18.14.0; manage Yarn with Corepack.

Corepack manages multiple per-project version of Yarn and PNPM, which
means we have to maintain less installation code, and could help us
switch away from Yarn 1 without making the system unusable for
development of other Yarn 1 projects.

https://nodejs.org/api/corepack.html

The Unicode spaces in the timerender test resulted from an ICU
upgrade: https://github.com/nodejs/node/pull/45068.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

scripts/lib/install-node

@@ -1,23 +1,24 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
-version=18.12.1
+version=18.14.0
 arch="$(uname -m)"
 
 case $arch in
     x86_64)
         tarball="node-v$version-linux-x64.tar.xz"
-        sha256=4481a34bf32ddb9a9ff9540338539401320e8c3628af39929b4211ea3552a19e
+        sha256=1ccec74b6240fce8754813e31fdbc93ad520df2e814729cea29efe9075e48350
         ;;
 
     aarch64)
         tarball="node-v$version-linux-arm64.tar.xz"
-        sha256=3904869935b7ecc51130b4b86486d2356539a174d11c9181180cab649f32cd2a
+        sha256=30ef375f0b8006759c0e08bee9d4b74915b95abfa924006c289d2d474a8b152e
         ;;
 esac
 
 check_version() {
-    out="$(node --version)" && [ "$out" = "v$version" ]
+    out="$(node --version)" && [ "$out" = "v$version" ] \
+        && [ /usr/local/bin/yarn -ef /srv/zulip-node/lib/node_modules/corepack/dist/yarn.js ]
 }
 
 if ! check_version 2>/dev/null; then
@@ -33,7 +34,11 @@ if ! check_version 2>/dev/null; then
     rm -rf /srv/zulip-node
     mkdir -p /srv/zulip-node
     tar -xJf "$tarball" --no-same-owner --strip-components=1 -C /srv/zulip-node
-    ln -sf /srv/zulip-node/bin/{node,npm,npx} /usr/local/bin
-    rm -rf /usr/local/nvm
+    ln -sf /srv/zulip-node/bin/{corepack,node,npm,npx} /usr/local/bin
+    COREPACK_DEFAULT_TO_LATEST=0 /usr/local/bin/corepack enable
+
+    # Clean up after previous versions of this script
+    rm -rf /srv/zulip-yarn /usr/bin/yarn /usr/local/nvm
+
     check_version
 fi