refactor: share inbound envelope label helper

src/signal/monitor/event-handler.ts

@@ -8,7 +8,7 @@ import {
   type ResponsePrefixContext,
 } from "../../auto-reply/reply/response-prefix-template.js";
 import { hasControlCommand } from "../../auto-reply/command-detection.js";
-import { formatInboundEnvelope } from "../../auto-reply/envelope.js";
+import { formatInboundEnvelope, formatInboundFromLabel } from "../../auto-reply/envelope.js";
 import {
   createInboundDebouncer,
   resolveInboundDebounceMs,
@@ -65,13 +65,14 @@ export function createSignalEventHandler(deps: SignalEventHandlerDeps) {
   };
 
   async function handleSignalInboundMessage(entry: SignalInboundEntry) {
-    // For groups: use group name or just "Group" (channel "Signal" is already shown).
-    // For DMs: keep headers compact; only add id: suffix if display differs from name.
-    const fromLabel = entry.isGroup
-      ? `${entry.groupName || "Group"} id:${entry.groupId}`
-      : entry.senderName === entry.senderDisplay
-        ? entry.senderName
-        : `${entry.senderName} id:${entry.senderDisplay}`;
+    const fromLabel = formatInboundFromLabel({
+      isGroup: entry.isGroup,
+      groupLabel: entry.groupName ?? undefined,
+      groupId: entry.groupId ?? "unknown",
+      groupFallback: "Group",
+      directLabel: entry.senderName,
+      directId: entry.senderDisplay,
+    });
     const body = formatInboundEnvelope({
       channel: "Signal",
       from: fromLabel,