Copy Link button hardcodes the production URL instead of using getSiteUrl()

[royalpinto007]

The "Copy Link" button on a case page builds the copied URL from a hardcoded string:

components/post/CopyLinkButton.tsx

navigator.clipboard.writeText(
  `https://agentpostmortem.com/case/${caseNumber}`,
);

The repo already has a helper for this in lib/utils/urls.ts (getSiteUrl()), which prefers NEXT_PUBLIC_SITE_URL, falls back to NEXT_PUBLIC_APP_URL, strips trailing slashes, and only then falls back to the production domain. Two problems with the hardcoded version: copying a link while developing on localhost:3000 gives you a production URL, and the canonical site is www.agentpostmortem.com while the button emits the apex domain.

What to do

1. Import getSiteUrl from @/lib/utils/urls in components/post/CopyLinkButton.tsx.
2. Use it to build the copied URL: ${getSiteUrl()}/case/${caseNumber}.
3. Check whether any other component hardcodes https://agentpostmortem.com in client code and fix those the same way (grep -rn "https://agentpostmortem.com" components app). Leave the intentional default inside lib/utils/urls.ts alone.

Verify

npm run lint
npx tsc --noEmit
npm run format
npm test

Then run npm run dev, open any case page, click Copy Link, and confirm the pasted URL points at your local origin.