feat: Gateway-API as an alternative to the Ingress in five annotation charts

Group 2 of the #114 sweep: the charts whose behaviour hangs off an nginx
annotation - calibre-web-automated, outline, paperless-ngx, zipline
(proxy-body-size) and freesailarr (rewrite-target).

Each gets the form the pilot (cyberchef, PR #115) fixed and group 1 (PR #116)
repeated: an httpRoute block off by default, a template rendering ONLY an
HTTPRoute with parentRefs - no Gateway, no gatewayClassName, no Certificate, no
implementation-specific policy object - render aborts on both modes at once
(naming both value paths), on an empty parentRefs and on a missing hostname,
empty hostnames meaning [ingress.domain], a schema entry closed against unknown
keys with an open parentRef definition, and a NOTES.txt that names the active
mode and what the mode costs.

Minor, additive, defaults unchanged: `helm template` with each chart's CI values
is byte-identical to origin/main for all five.

The upload limit is DOCUMENTED, not rebuilt (decision 2 of the issue). The
Gateway API knows no body size; a policy object would bind the chart to one
implementation. So the Gateway branch of NOTES.txt says, per chart and in the
chart's own terms, that the value is NOT ENFORCED and names where to set it: an
e-book library (calibre), an upload service (zipline), the web-UI half of the
document intake while the consume directory keeps no limit at all (paperless),
and the open #12 pair (outline).

Four findings that were not in the plan, each argued in the file it changes:

  freesailarr gated freesailarr.sharedIngressApps on ingress.enabled, and that
  list is read by the <APP>__SERVER__URLBASE variables as well as by the routing
  objects. In Gateway mode it would have come out EMPTY while the route served
  radarr, sonarr and prowlarr under their prefixes: UrlBase unset, assets and API
  calls linked at the host root, broken UI behind a Ready pod. The helper's two
  guards (seerr/mediathekarr only at "/", no duplicate paths) would have gone
  unenforced there too. Fixed with freesailarr.published (ingress.enabled OR
  httpRoute.enabled) - the same shape as sure.publishedOverTls in group 1, and
  identical to ingress.enabled while httpRoute.enabled is false. Measured: on
  origin/main with ingress.enabled: false the render emits ZERO URLBASE
  variables; with this change in Gateway mode it emits three.

  paperless-ngx was the last chart in the repository rendering its Ingress
  UNCONDITIONALLY. Without an ingress.enabled switch there is no second value
  path for the mutual-exclusion abort to name, and the Ingress plus its
  unconditional required() on clusterIssuer would have kept rendering in Gateway
  mode - a value demanded for nothing, which is issue #114's "Folge 1" and
  README guideline 12. The switch was added, defaulting to true, so the render is
  unchanged.

  paperless-ngx PAPERLESS_URL had no required() of its own: it relied on the
  Ingress template's, which stops firing the moment the Ingress is switchable.
  With httpRoute.hostnames set and ingress.domain empty it would have rendered
  "https://" and refused every login POST as a CSRF failure. It now carries its
  own required(), naming what the value is for.

  calibre-web-automated claimed, in values.yaml and in its schema, that
  ingress.domain is read nowhere but in the Ingress template. The HTTPRoute reads
  it, so the claim now holds only while both modes are off. Corrected rather than
  left standing - the same correction garage needed in group 1.

freesailarr is where the Gateway API is LESS machinery than what it replaces,
not a translation of it. rewrite-target applies per Ingress OBJECT, so
qBittorrent (no base path, prefix must be stripped) needed a second Ingress on
the shared host, which then had to repeat the first object's TLS secret name,
omit the cert-manager annotation conditionally so only one Certificate is
requested, and match an ImplementationSpecific regex path for the rewrite's
capture group. A URLRewrite filter applies per RULE: one route, one rule per
app, the filter on qBittorrent's rule, a plain PathPrefix. All four crutches
gone. It is also the only chart without httpRoute.hostnames - it has no
ingress.domain either, and a chart-global hostname list could not say which of
the ten apps it belonged to, so the hostnames stay in ingress.host and
<app>.ingress.host.

CI: one render overlay per chart under ci/httproute/, so the assertion is not
vacuum-green - ci/run-httproute-match-test.sh goes from 20 held assertions over
10 charts to 36 over 15. freesailarr's overlay moves bazarr onto a host of its
own, so the shared-host route AND the per-app route are both rendered; without
that the per-app branch would be exercised by nothing. The install-test fixtures
stay in Ingress mode: the install runs one configuration per chart, cyberchef
already pays that price against the real Gateway-API CRDs, and for paperless-ngx
that fixture is the only install of the valkey-subchart path anywhere.

README also carries a stale figure fixed here: the HTTPRoute test was still
documented at the pilot's 4 assertions over 2 charts, although group 1 had taken
it to 20 over 10.

Not proven, by construction: that traffic flows. No Gateway controller runs in
CI. Not run locally either: k3d, Docker, Trivy. The Gateway branch of NOTES.txt
is EXECUTED by the render test (a template error in it fails the job, verified)
but its text is printed by no pipeline stage - helm template does not emit
notes, and the install-test installs in Ingress mode.

Part of #114

paperless-ngx/values.yaml

@@ -16,13 +16,88 @@ secrets:
   oidcSecretRef: null
 
 ingress:
+  # Set to false to omit the Ingress entirely. NEW in the chart version that
+  # added the httpRoute block below (Gitea #114): this chart used to render its
+  # Ingress unconditionally, which is why it has no issue-#93 switch like the
+  # rest. The default is true, so an existing release is unaffected.
+  #
+  # It was not added for uniformity. Without it the Ingress would keep
+  # rendering in Gateway mode, and with it the required() on clusterIssuer -
+  # a value demanded for something the chart then does not render. With the
+  # switch that required() is conditional, as everywhere else here.
+  #
+  # clusterIssuer becomes unnecessary with the Ingress off. ingress.domain does
+  # NOT: it is also PAPERLESS_URL, the only origin this release declares to
+  # Django, and it carries its own required() in the StatefulSet.
+  #
+  # Mutually exclusive with httpRoute.enabled below: with both true the render
+  # aborts, naming both values. Mind that enabled defaults to TRUE here, so
+  # turning the Gateway mode on means switching this off in the same values
+  # file.
+  enabled: true
   clusterIssuer: null
+  # The public hostname of this release. Read by the Ingress, by PAPERLESS_URL
+  # in the StatefulSet (with its own required()), and - when
+  # httpRoute.hostnames is empty - by the HTTPRoute. Required in every mode.
   domain: null
   className: nginx
   # Extra annotations for the Ingress; merged with the cert-manager
   # cluster-issuer and upload-size annotations the chart always sets.
+  #
+  # THESE HAVE NO COUNTERPART IN GATEWAY MODE. The Gateway API has no
+  # annotation channel for controller behaviour, so anything configured here is
+  # simply gone when httpRoute.enabled is used instead - it is then the
+  # Gateway's business, or that of an implementation-specific policy object
+  # this chart deliberately does not render. For THIS chart that includes the
+  # upload cap: see paperless.files.maxUploadFileSize.
   annotations: {}
 
+# Gateway-API alternative to the Ingress above (Gitea #114). Off by default, so
+# an existing release is unaffected; exactly one of ingress.enabled and
+# httpRoute.enabled may be true - and ingress.enabled defaults to true, so it
+# has to be switched off explicitly.
+#
+# The chart renders ONLY an HTTPRoute with parentRefs - no Gateway, no
+# gatewayClassName, no Certificate and no implementation-specific policy
+# object. Class and certificate belong to the Gateway and therefore to the
+# platform, which is what keeps this chart independent of whether the cluster
+# runs nginx-gateway-fabric, Cilium, Envoy Gateway or Istio.
+#
+# WHAT THIS MODE COSTS HERE: paperless.files.maxUploadFileSize is not enforced,
+# so the web UI's upload ceiling is the Gateway's. The consume directory is
+# unaffected - it passes no proxy and has no limit at all.
+#
+# The Gateway-API CRDs must be installed in the cluster: the chart does not and
+# cannot detect them (.Capabilities.APIVersions is unreliable at template
+# time), so with httpRoute.enabled: true and no CRDs the INSTALL fails.
+httpRoute:
+  enabled: false
+  # The Gateway(s) this route attaches to - a platform object, usually in
+  # another namespace, which must allow this namespace in its listener's
+  # allowedRoutes. One entry per parent, the fields are the Gateway API's
+  # ParentReference (name, and optionally namespace, sectionName, port, group,
+  # kind), passed through unchanged:
+  #
+  #   parentRefs:
+  #     - name: public
+  #       namespace: gateway
+  #       sectionName: https
+  #
+  # REQUIRED while httpRoute.enabled is true - the render aborts on an empty
+  # list, because a route without a parent is created, is valid and routes
+  # nothing, with no event to say so.
+  parentRefs: []
+  # Empty means [ingress.domain], so the hostname has one source of truth. Set
+  # explicitly only to publish under a different or an additional name - which
+  # is how a migration from the Ingress runs: the HTTPRoute takes a second
+  # hostname while the Ingress keeps ingress.domain.
+  #
+  # For THIS chart, mind that a second hostname does not move PAPERLESS_URL
+  # with it: Django keeps trusting the origin built from ingress.domain, and
+  # every login POST from the new name is refused as a CSRF failure until that
+  # value is changed too (and the pods restarted).
+  hostnames: []
+
 paperless:
   # Replica count for this workload; 0 is allowed and scales it down.
   # The chart-global scaleDown flag takes precedence.