Add .npmrc to work around stale peer dep in starlight-client-mermaid

Author: maartenba

astro/.npmrc

@@ -0,0 +1,6 @@
+# @pasqal-io/starlight-client-mermaid@0.1.0 has a stale peer dep on
+# @astrojs/markdown-remark@^6.0.2 which conflicts with the ^7.1.0 required
+# by Astro 6 / Starlight 0.38. The package works fine at runtime.
+# Remove this once starlight-client-mermaid publishes a version with an
+# updated peer dependency range.
+legacy-peer-deps=true