feat(rss-bridge): networkPolicy.ingress.ambientMesh

Gitea #143. Additive, default false, so the render is byte-identical to the
previous release - proven by diffing both renders against origin/main rather
than asserted.

Switched on it adds 15008/TCP, ztunnel's HBONE tunnel, to the rule carrying
the probe port, and - inside that rule's source-restricted branch -
169.254.7.127/32, the address the kubelet's probes arrive from once the pod is
in the mesh. Ambient does not bypass NetworkPolicy enforcement, so without the
port a pod whose namespace has joined the mesh is unreachable.

The two halves are one value because the second is the one nobody thinks of:
15008 added by hand leaves a policy that passes review and drops every probe
the first time probeSources is narrowed, and a pod that never becomes Ready
reads as a broken application rather than as a policy.

Minor, not major: additive value, unchanged default, unchanged render.

rss-bridge/Chart.yaml

@@ -5,7 +5,7 @@ icon: https://raw.githubusercontent.com/RSS-Bridge/rss-bridge/master/static/logo
 
 type: application
 
-version: 3.0.0+up2026.09.30
+version: 3.1.0+up2026.09.30
 appVersion: "2026-09-30"
 
 maintainers: