fix(deps): revert astro to v5.18.0 - blocked by @astrojs/starlight incompatibility with v6

[Copilot]

The renovate-generated astro v6 update broke CI in two ways: package-lock.json was never regenerated to match the package.json bump, and even with a correct lock file, @astrojs/starlight@0.37.7 (latest) declares a peer dependency of astro@^5.5.0 — making it fundamentally incompatible with astro v6 (fails at config setup with an internal zod v4 conflict).

Changes

• docs/package.json — Reverts astro from ^6.0.0 back to ^5.18.0 (latest stable v5)
• docs/package-lock.json — Regenerated via npm install to be in sync with package.json

The astro v6 upgrade should be re-attempted once @astrojs/starlight releases a compatible version.

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[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• telemetry.astro.build
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node node /home/REDACTED/work/monorepo/monorepo/docs/node_modules/.bin/astro build (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
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