fix(nginx): return a real 404 instead of a 500 redirect loop

The 404 fallback pointed at /404/index.html, but Astro emits 404.html,
so every unknown URL looped internally and nginx answered 500. The
try_files fallback also served the error page with a 200 status.
Fall through to =404 and point error_page at /404.html.

deploy/nginx.conf

@@ -14,10 +14,10 @@ server {
   }
 
   location / {
-    try_files $uri $uri/ /404/index.html;
+    try_files $uri $uri/ =404;
   }
 
-  error_page 404 /404/index.html;
+  error_page 404 /404.html;
 
   location ~* \.(?:css|js|jpg|jpeg|png|webp|svg|ico|woff2)$ {
     try_files $uri =404;

docs/launch-checklist.md

@@ -81,10 +81,20 @@ visitor → Cloudflare DNS (bluecapstrategies.com)
 #### Prerequisites (all invisible to the public; the old site keeps serving)
 - [x] Cloudflare token now covers the zone — `7tl-homelab.com`, **`bluecapstrategies.com`**,
       `rodgersweb.com` (done 2026-10-09). Token is DNS-edit-only, which is correct least privilege.
-- [ ] **k3s ingress:** add `www.bluecapstrategies.com` + `bluecapstrategies.com` to the `tls:`
+- [x] **k3s ingress — DONE 2026-10-09 (commit `6f80282`).** Both production hostnames added to
-      block in `k8s/ingress.yaml` (issuer annotation is already present and correct —
+      the `tls:` block as `bluecap-website-tls`. Certificate **Ready**, issued by Let's Encrypt
-      `letsencrypt-prod`). cert-manager pre-issues via DNS-01, so do this **before** cutover and
+      via DNS-01: `CN=www.bluecapstrategies.com`, SANs `bluecapstrategies.com` +
-      confirm the Certificate goes Ready. Needed because Pangolin proxies to **https:443**.
+      `www.bluecapstrategies.com`, valid to **2027-01-07**, auto-renewing. Verified the cluster
+      serves it for both names (`--resolve` straight to 10.66.15.30 → 200, correct cert, rebuild
+      content). The public site is untouched and still on Cloudflare/Bluehost throughout.
+      Both names are on one cert, so the canonical-host decision stays open.
+      - Issuance stalled ~4h: the TXT records were present in Cloudflare's API immediately but
+        Cloudflare's own authoritative nameservers returned NXDOMAIN for them for a long while.
+        It cleared on its own. If this recurs, cert-manager's DNS-01 self-check resolver is the
+        thing to look at — it is currently CoreDNS (`nameservers=["10.43.0.10:53"]`), and the
+        usual hardening is to point it at public resolvers instead:
+        `--dns01-recursive-nameservers-only=true --dns01-recursive-nameservers=1.1.1.1:53,8.8.8.8:53`.
+        Worth doing before cutover day so renewals do not inherit this fragility (§2.7).
 - [ ] **Pangolin:** add `bluecapstrategies.com` as a domain under org **`rhh-homelab`**
       (`orgDomains`), `certResolver=letsencrypt`.
 - [ ] **Pangolin:** create the resource(s) with **three targets**, matching the established
@@ -97,6 +107,19 @@ visitor → Cloudflare DNS (bluecapstrategies.com)
 - [ ] **Test before any DNS change:** `curl --resolve bluecapstrategies.com:443:23.94.111.133`
       and confirm the full path serves the site.
 
+#### Pangolin resource targets (for step 2)
+Three targets, matching every other k3s-backed resource:
+
+| Target | Method | Port |
+|--------|--------|------|
+| `10.66.15.30` | https | 443 |
+| `10.66.15.31` | https | 443 |
+| `10.66.15.32` | https | 443 |
+
+`k3-control-1/2/3`. Three gives node-level failover. Set the host header to the real hostname so
+k3s traefik routes on it. The cluster now holds a valid cert for both production names, so the
+https hop verifies properly.
+
 #### Proxied vs DNS-only — decide before cutover 🛑
 The zone is currently **proxied**: apex `A → 50.87.136.52 PROXIED`, `www CNAME → apex PROXIED`.
 
@@ -270,6 +293,18 @@ say depends on the owner's call in §1.5 on whether `/insights/` ships at all.
 - [ ] If `/insights/` ships: delete both note-cards and rewrite the hero as reader-facing copy.
 - [ ] If it does not: drop it from the primary nav and exclude the route from the sitemap.
 
+### 2.7 cert-manager DNS-01 self-check uses CoreDNS
+`cert-manager` logs `configured acme dns01 nameservers nameservers=["10.43.0.10:53"]`, i.e. it
+validates DNS-01 propagation through the cluster's own CoreDNS rather than public resolvers. That
+makes issuance sensitive to internal caching — including negative caching of the `_acme-challenge`
+name it is waiting on.
+
+- [ ] Point it at public resolvers before cutover:
+      `--dns01-recursive-nameservers-only=true --dns01-recursive-nameservers=1.1.1.1:53,8.8.8.8:53`.
+      Not confirmed as the cause of the 4h stall on 2026-10-09 (Cloudflare's authoritative NS were
+      themselves returning NXDOMAIN for records its API reported as present), but it is the
+      standard hardening and removes one variable from certificate renewal.
+
 ### 2.6 Staging URL ✅ LIVE 2026-09-23
 **https://bcs.int.7tl-homelab.com** — review the rebuild in a browser, valid cert, no warning.