Pin sitemap URLs to https; bump to 2.8.2 (#1252)

[jonfroehlich]

Refs #1252. Final follow-up before the prod release.

What the test-server validation found

After #1309 deployed to -test, I crawled the live sitemap:

• ✅ XML well-formed, 189 URLs, all on the correct host.
• ✅ robots.txt now served with today's Last-Modified and the Sitemap: line (confirms the repo's static ./robots.txt is the served file).
• ⚠️ Every <loc> was an http:// URL that 302-redirects to https://. Following the redirects, all 189/189 return 200 — no dead links — but advertising non-canonical http URLs with an extra hop is bad for SEO.

Cause: Apache terminates TLS and proxies to Django over plain HTTP, so RequestSite sees the http request scheme.

Fix

• Add an _HttpsSitemap base class (protocol = "https") and have all four sitemaps extend it, so <loc> URLs are canonical https://.
• Add a regression test asserting every <loc> uses https.
• Bump 2.8.1 → 2.8.2; release description notes the fix and the 189/189 → 200 validation.

Testing

• Ran 7 tests in test_sitemap.py, all pass; full suite green.
• Verified locally the sitemap now emits https://… <loc> URLs.

Validation summary (on -test, before this fix)

Check	Result
sitemap.xml well-formed	✅
URL count	189 (< 50k limit)
All on correct host	✅
All URLs reachable (final)	✅ 189/189 → 200
robots.txt advertises sitemap	✅
<loc> scheme	⚠️ http → fixed to https here

After this merges to -test I'll re-curl to confirm https <loc>s, then this same 2.8.2 is ready to tag for production.

🤖 Generated with Claude Code