Say every forge event on the bus through a signed system webhook, and announce a head or merge at once (novox/hq issue 729)

The gitea module keeps one system webhook for every event family, made or
corrected at start with the admin account (POST /admin/hooks, forge 1.27.3)
and a secret it mints and keeps. Its receiver, at the docker bridge's
gateway, refuses an unsigned request before reading it, a body over 5 MB,
and a signature that does not verify; it answers a verified delivery at once,
drops one already heard by its delivery id, and publishes each as
forge.<kind>.<action> on the module's events (its own stream, ADR 0363,
follows issue 725). A pull request opened, pushed to or merged is announced
at once. The polls look every five minutes only while deliveries arrive, and
every 30 s again, saying so loudly, when one finds what no event said or ten
minutes pass without a delivery. The announced records keep both paths from
announcing twice.

modules/gitea/module.json

@@ -42,7 +42,47 @@
     "issue.opened",
     "pull.merged",
     "pull.updated",
-    "pull.closed"
+    "pull.closed",
+    "forge.push",
+    "forge.create",
+    "forge.delete",
+    "forge.fork",
+    "forge.status",
+    "forge.pull-request.opened",
+    "forge.pull-request.reopened",
+    "forge.pull-request.synchronized",
+    "forge.pull-request.edited",
+    "forge.pull-request.closed",
+    "forge.pull-request.merged",
+    "forge.pull-request.labeled",
+    "forge.pull-request.unlabeled",
+    "forge.pull-request.assigned",
+    "forge.pull-request.unassigned",
+    "forge.pull-request.reviewed",
+    "forge.pull-request.review-requested",
+    "forge.pull-request.commented",
+    "forge.pull-request.changed",
+    "forge.issue-comment.created",
+    "forge.issue-comment.edited",
+    "forge.issue-comment.deleted",
+    "forge.issues.opened",
+    "forge.issues.reopened",
+    "forge.issues.closed",
+    "forge.issues.edited",
+    "forge.issues.labeled",
+    "forge.issues.unlabeled",
+    "forge.issues.assigned",
+    "forge.issues.unassigned",
+    "forge.issues.changed",
+    "forge.release.published",
+    "forge.release.updated",
+    "forge.release.deleted",
+    "forge.release.changed",
+    "forge.repository.created",
+    "forge.repository.deleted",
+    "forge.repository.changed",
+    "forge.wiki.changed",
+    "forge.other"
   ],
   "consumes": [
     "mesh-controller.checked",
@@ -61,7 +101,14 @@
       "port": 22,
       "protocol": "tcp",
       "from": "mesh",
-      "why": "git over ssh, gitea's own unmodified sshd. Published on the machine's own side at 222, the mesh's fixed public convention \u2014 not 22, which the machine's own daemon holds and a module does not take"
+      "why": "git over ssh, gitea's own unmodified sshd. Published on the machine's own side at 222, the mesh's fixed public convention — not 22, which the machine's own daemon holds and a module does not take"
+    },
+    {
+      "name": "forge-events",
+      "port": 3047,
+      "protocol": "tcp",
+      "from": "machine",
+      "why": "the forge's system webhook, every event signed with a secret the module keeps, from the forge's container on the docker bridge to the module's receiver at the bridge's gateway 172.17.0.1 (novox/hq issue 729)"
     }
   ],
   "serves": {
@@ -153,7 +200,7 @@
       "type": "file",
       "path": "${dir:state}/server.env",
       "mode": "0600",
-      "content": "GITEA__security__INTERNAL_TOKEN=${secret:internal-token}\nGITEA__database__DB_TYPE=postgres\nGITEA__database__HOST=${bound:postgres-database:at}:${bound:postgres-database:port}\nGITEA__database__NAME=${bound:postgres-database:as}\nGITEA__database__USER=${bound:postgres-database:as}\nGITEA__database__PASSWD=${secret:postgres-database}\n"
+      "content": "GITEA__security__INTERNAL_TOKEN=${secret:internal-token}\nGITEA__database__DB_TYPE=postgres\nGITEA__database__HOST=${bound:postgres-database:at}:${bound:postgres-database:port}\nGITEA__database__NAME=${bound:postgres-database:as}\nGITEA__database__USER=${bound:postgres-database:as}\nGITEA__database__PASSWD=${secret:postgres-database}\nGITEA__webhook__ALLOWED_HOST_LIST=172.17.0.1\n"
     },
     {
       "id": "data",
@@ -263,7 +310,10 @@
           "MESH_GITEA_ADMIN_PASSWORD_FILE": "${dir:state}/admin.secret",
           "MESH_GITEA_STATE_DIR": "${dir:runtime-state}",
           "MESH_RECEIVES": "${dir:grants}/npm.json",
-          "MESH_GITEA_READY_AUTHORS_FILE": "${dir:mesh-state}/ready-authors"
+          "MESH_GITEA_READY_AUTHORS_FILE": "${dir:mesh-state}/ready-authors",
+          "MESH_GITEA_HOOK_URL": "http://172.17.0.1:3047",
+          "MESH_GITEA_HOOK_PORT": "3047",
+          "MESH_GITEA_HOOK_HOST": "172.17.0.1"
         }
       },
       {