feat(groups): optional forge source label in message footers

- Group.forgeLabel (default off, editable per group in the console) shows the
  source forge on every message the group's routes dispatch
- Discord embed footer: forge name next to the repo + the site's favicon as
  icon_url (Gitea instance's own favicon from its origin)
- Telegram footer: hyperlinked site name (GitHub or Gitea hostname); custom
  webhooks render a plain 'Custom' label
- forgeInfo() derives branding from event.provider + repository.html_url;
  dispatch attaches it to the NeutralMessage like mentionRoleIds
- validateGroups accepts forgeLabel booleans; GroupEditor gains the toggle
- tests: forgeInfo unit, discord/telegram footer render, dispatch on/off
- docs: groups.md + message-format.md (en/zh), config.example.yaml, AGENTS.md
- fix: wrangler.jsonc compatibility_date was an incomplete '2026-'

server/lib/core/dispatch.ts

@@ -1,6 +1,6 @@
 import type { Config, WebhookEvent, Env, Route, Group, NeutralMessage } from "../types";
 import { formatEvent } from "../formatters";
-import { emojiPrefix } from "../formatters/helpers";
+import { emojiPrefix, forgeInfo } from "../formatters/helpers";
 import { matchRoute, eventOwners } from "../events/match";
 import { log } from "../lib/log";
 import { loadTranslations, t as translate, type Translations } from "../lib/i18n";
@@ -156,6 +156,9 @@ export async function dispatchEvent(
     const tr = trMap.get(group?.lang ?? "en")!;
     const showEmoji = group?.emoji !== false;
     const message = formatEvent(route, event, tr, showEmoji);
+    if (group?.forgeLabel) {
+      message.forge = forgeInfo(event);
+    }
     if (route.discordRoleIds?.length) {
       message.mentionRoleIds = route.discordRoleIds;
     }

server/lib/drivers/discord/render.ts

@@ -39,6 +39,10 @@ export function renderNeutralMessage(message: NeutralMessage): FormattedMessage
 
   // Safety net: clamp every embed part to the Discord API limits so a single
   // oversized formatter or custom payload can never hard-fail the request.
+  const footerText = cap(
+    [message.forge?.name, message.footer].filter(Boolean).join(" · "),
+    MAX_FOOTER,
+  );
   return {
     content,
     embeds: [
@@ -61,7 +65,9 @@ export function renderNeutralMessage(message: NeutralMessage): FormattedMessage
             value: cap(f.value, MAX_FIELD_VALUE),
             inline: f.inline,
           })),
-        footer: message.footer ? { text: cap(message.footer, MAX_FOOTER) } : undefined,
+        footer: footerText
+          ? { text: footerText, icon_url: message.forge?.iconUrl }
+          : undefined,
         timestamp: message.timestamp,
       },
     ],

server/lib/drivers/telegram/render.ts

@@ -89,6 +89,10 @@ export function renderNeutralMessage(message: NeutralMessage): string {
   }
 
   const meta: string[] = [];
+  if (message.forge) {
+    const name = mdToHtml(message.forge.name);
+    meta.push(message.forge.url ? `<a href="${esc(message.forge.url)}">${name}</a>` : name);
+  }
   if (message.footer) meta.push(esc(message.footer));
   const ts = formatTimestamp(message.timestamp);
   if (ts) meta.push(ts);

server/lib/formatters/helpers.ts

@@ -1,4 +1,4 @@
-import type { NeutralMessage } from "../types";
+import type { NeutralForge, NeutralMessage, WebhookEvent } from "../types";
 import { t as translate } from "../lib/i18n";
 import type { Translations } from "../lib/i18n";
 
@@ -160,3 +160,29 @@ export function senderProfileUrl(repoUrl: string | undefined, login: string): st
   }
   return `https://github.com/${login}`;
 }
+
+/**
+ * Forge branding for an event (used when the group enables `forgeLabel`):
+ * GitHub gets its brand + favicon, Gitea the instance hostname + favicon
+ * derived from the repository URL, custom webhooks a plain "Custom" label.
+ */
+export function forgeInfo(event: WebhookEvent): NeutralForge | undefined {
+  const repoUrl = (event.payload.repository as { html_url?: string } | undefined)?.html_url;
+  switch (event.provider) {
+    case "github":
+      return { name: "GitHub", url: "https://github.com", iconUrl: "https://github.com/favicon.ico" };
+    case "gitea": {
+      if (!repoUrl) return undefined;
+      try {
+        const origin = new URL(repoUrl).origin;
+        return { name: new URL(origin).hostname, url: origin, iconUrl: `${origin}/favicon.ico` };
+      } catch {
+        return undefined;
+      }
+    }
+    case "custom":
+      return { name: "Custom" };
+    default:
+      return undefined;
+  }
+}

server/lib/types.ts

@@ -126,6 +126,11 @@ export interface Group {
    * Defaults to true when omitted.
    */
   emoji?: boolean;
+  /**
+   * Whether to show the forge source (GitHub / Gitea instance / custom) in the
+   * footer of this group's messages. Defaults to false when omitted.
+   */
+  forgeLabel?: boolean;
   /**
    * Message language for every route in this group (e.g. "en", "zh"; custom
    * via KV i18n:<lang>). Defaults to "en" when omitted.
@@ -165,6 +170,20 @@ export interface NeutralAuthor {
   url?: string;
 }
 
+/**
+ * The forge (source platform) that produced an event: shown in the message
+ * footer when the group enables `Group.forgeLabel` so recipients can tell
+ * GitHub, a Gitea instance or a custom webhook apart at a glance.
+ */
+export interface NeutralForge {
+  /** Display name, e.g. "GitHub" or the Gitea instance hostname. */
+  name: string;
+  /** Site URL for the hyperlink (Telegram) / brand context (Discord). */
+  url?: string;
+  /** Site favicon used as the Discord embed footer icon. */
+  iconUrl?: string;
+}
+
 export interface NeutralField {
   name: string;
   value: string;
@@ -189,6 +208,11 @@ export interface NeutralMessage {
   footer?: string;
   timestamp?: string;
   actions?: NeutralAction[];
+  /**
+   * Forge branding set by dispatch when `Group.forgeLabel` is enabled; drivers
+   * render it in the footer (Discord icon + name, Telegram linked name).
+   */
+  forge?: NeutralForge;
   /**
    * Stable key identifying a message chain that should be updated in place
    * (e.g. workflow run progress). When set, subsequent events edit the
@@ -215,7 +239,7 @@ export interface FormattedMessage {
       url?: string;
     };
     fields?: Array<{ name: string; value: string; inline?: boolean }>;
-    footer?: { text: string };
+    footer?: { text: string; icon_url?: string };
     timestamp?: string;
   }>;
   components?: Array<{

server/lib/web/admin.ts

@@ -301,6 +301,9 @@ export function validateGroups(
     if (g.emoji !== undefined && typeof g.emoji !== "boolean") {
       return { ok: false, error: `group "${g.id}".emoji must be a boolean` };
     }
+    if (g.forgeLabel !== undefined && typeof g.forgeLabel !== "boolean") {
+      return { ok: false, error: `group "${g.id}".forgeLabel must be a boolean` };
+    }
     if (g.lang !== undefined && typeof g.lang !== "string") {
       return { ok: false, error: `group "${g.id}".lang must be a string` };
     }