fix: pin html-webpack-plugin-5 alias to 5.6.4 in lockfile

The yarn alias html-webpack-plugin-5@npm:html-webpack-plugin@^5
resolved to 5.6.6 in the lockfile. The dependency-age-check tool
looks up html-webpack-plugin-5@5.6.6 on npm, which returns unusual
registry metadata that the tool cannot parse, causing the cooldown
CI job to fail deterministically.

Adds html-webpack-plugin-5 to resolutions to prevent future
re-upgrades, and pins the lockfile entry to 5.6.4 (matching
the existing html-webpack-plugin pin added for the same reason).

TICKET: VL-5111

Author: roshan-bitgo

package.json

@@ -120,6 +120,7 @@
     "memfs": "4.46.0",
     "// html-webpack-plugin": "cooldown check fails for yarn alias html-webpack-plugin-5 on npm due to unpublished package format; pin to previous version",
     "html-webpack-plugin": "5.6.4",
+    "html-webpack-plugin-5": "npm:html-webpack-plugin@5.6.4",
     "// @iota/iota-sdk": "1.11.0 raised engines to >=24; pin to 1.10.1 until CI baseline moves to Node 24",
     "@iota/iota-sdk": "1.10.1",
     "**/iota-sdk/**/valibot": "1.2.0",