feat(rust): the rewards — tally, kit reward, chat and the news leg (phase 13b, protocol 10)

Four event verbs and the announce leg, per PLAN.md §29:

- rust.participation.open / .collect: the plugin counts who takes part
  (seconds, kills or both, in a zone this run opened or the whole server)
  and collect files them as the run's participants, keyed by Steam id.
- rust.kit.entitle: the five recipient modes (D101), rows in the new
  rust_perm_run_grants (D84) unioned into the permission push, one extra
  use of the kit per reward as site-held credits on perm.sync (D103),
  and the rust.kit.entitled notice deferred from phase 10 (D64).
- rust.announce: one server or every server (D105).
- rust.chat announce leg, speaking only on servers whose new news switch
  is on (D104) - a card on Admin -> Rust visibility (D106).

Budgets rust.grants and rust.announcements; the kit source and four
fixed-choice sources (core has no enum param type). rust_perm_run_grants
carries core's idempotency key so a revert of a lost answer can find its
rows. Protocol 10.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

engagement-triggers.json

@@ -316,6 +316,81 @@
         }
       ]
     },
+    {
+      "id": "rust.kit.entitled",
+      "label": "An event rewarded you a kit",
+      "description": "An event on a Rust server rewarded you: a kit is waiting in the in-game Kits menu, with one extra use.",
+      "kind": "event",
+      "subjectKey": "rewardKey",
+      "audience": "owner",
+      "ceiling": "owner",
+      "version": 1,
+      "variables": [
+        {
+          "name": "title",
+          "type": "string",
+          "required": false,
+          "example": "Main is back online",
+          "description": "A one-line headline naming what happened and where. Core generic bodies use it as the title."
+        },
+        {
+          "name": "intro",
+          "type": "string",
+          "required": false,
+          "example": "Main is back up and taking players.",
+          "description": "One sentence of detail. Core generic bodies use it as the body."
+        },
+        {
+          "name": "rewardKey",
+          "type": "string",
+          "required": true,
+          "example": "41:7",
+          "description": "The run and step that awarded it. The cooldown subject; not meant for display."
+        },
+        {
+          "name": "kit",
+          "type": "string",
+          "required": true,
+          "example": "vip-starter",
+          "description": "The kit name, as the server Kits plugin has it."
+        },
+        {
+          "name": "serverId",
+          "type": "string",
+          "required": true,
+          "example": "main",
+          "description": "The server the event happened on, as configured in Admin -> Rust. Also the cooldown subject for broadcasts."
+        },
+        {
+          "name": "server",
+          "type": "string",
+          "required": true,
+          "example": "Runic Gateway | Main",
+          "description": "The server's display name."
+        },
+        {
+          "name": "serverUrl",
+          "type": "url",
+          "required": false,
+          "example": "/rust/servers/main",
+          "description": "Site-relative path to the server's page."
+        },
+        {
+          "name": "mode",
+          "type": "string",
+          "required": false,
+          "example": "top",
+          "description": "How the recipients were chosen: everyone, top, minScore, random or topPercent."
+        },
+        {
+          "name": "accountUrl",
+          "type": "url",
+          "required": false,
+          "example": "/player/rust",
+          "description": "Site-relative path to your Rust account page."
+        }
+      ]
+    },
     {
       "id": "rust.leaderboard.topped",
       "label": "A new kills leader",
@@ -1059,6 +1134,28 @@
         }
       ]
     },
+    {
+      "key": "rewards-v1",
+      "rules": [
+        {
+          "trigger_id": "rust.kit.entitled",
+          "audience": "owner",
+          "channels": [
+            "email",
+            "inapp"
+          ],
+          "template_keys": {
+            "email": "notify.event",
+            "inapp": "inapp.event",
+            "digest": "notify.digest"
+          },
+          "conditions": null,
+          "cooldown_seconds": 0,
+          "delay_seconds": 0,
+          "cancel_on": []
+        }
+      ]
+    },
     {
       "key": "clans-v1",
       "rules": [