fix(ci): smoke test accepts release-assets CDN hostname (#509)

v2.0.4 rerun of update-apt-repo made it past hops 0 and 1 (the smoke
test scheme fix in #506 worked — Pages' http:// redirect no longer
trips the chain walker), but failed on hop 2:

  Hop 2: 302 .../releases/download/v2.0.4+claude1.3883.0/...deb
         -> https://release-assets.githubusercontent.com/...
  ::error::Hop 2 mismatch: expected https://objects\.githubusercontent\.com/,
           got https://release-assets.githubusercontent.com/...

GitHub migrated the Release asset CDN from objects.githubusercontent.com
to release-assets.githubusercontent.com (both have been serving in the
past; release-assets is the current canonical hostname). Accept either
hostname via alternation.

Verified against the actual v2.0.4 Release:
  $ curl -Is https://github.com/aaddrick/claude-desktop-debian/releases/download/v2.0.4+claude1.3883.0/claude-desktop_1.3883.0-2.0.4_amd64.deb \
    | grep -i location
  location: https://release-assets.githubusercontent.com/github-production-release-asset/...

Same fix in three sites:
- .github/workflows/ci.yml (update-apt-repo smoke test)
- .github/workflows/ci.yml (update-dnf-repo smoke test)
- .github/workflows/apt-repo-heartbeat.yml (daily heartbeat)

docs/worker-apt-plan.md has historical references to
objects.githubusercontent.com too; those can be updated in a follow-up
docs sweep — the architectural claim (binary bytes flow direct from
GitHub CDN, never through Cloudflare) is unchanged.

Refs #493, #503

Author: aaddrick

.github/workflows/apt-repo-heartbeat.yml

@@ -91,7 +91,7 @@ jobs:
           expected_hops=(
             "https?://${WORKER_DOMAIN}/"
             "https://github\\.com/aaddrick/claude-desktop-debian/releases/download/"
-            "https://objects\\.githubusercontent\\.com/"
+            "https://(objects|release-assets)\\.githubusercontent\\.com/"
           )
           url="$URL"
           for i in "${!expected_hops[@]}"; do

.github/workflows/ci.yml

@@ -537,7 +537,7 @@ jobs:
           expected_hops=(
             "https?://${WORKER_DOMAIN}/"
             "https://github\\.com/aaddrick/claude-desktop-debian/releases/download/v${repoVer}\\+claude${claudeVer}/"
-            "https://objects\\.githubusercontent\\.com/"
+            "https://(objects|release-assets)\\.githubusercontent\\.com/"
           )
           url="$deb_url"
           for i in "${!expected_hops[@]}"; do
@@ -751,7 +751,7 @@ jobs:
           expected_hops=(
             "https?://${WORKER_DOMAIN}/"
             "https://github\\.com/aaddrick/claude-desktop-debian/releases/download/v${repoVer}\\+claude${claudeVer}/"
-            "https://objects\\.githubusercontent\\.com/"
+            "https://(objects|release-assets)\\.githubusercontent\\.com/"
           )
           url="$rpm_url"
           for i in "${!expected_hops[@]}"; do