feat(calls): "Call ended · 41 min · connection was good" toast (#143)

One line in the existing toast style when a call you were in ends: the
duration from our own join clock, plus the fork's io.lotus.call_summary
readout (fork ≥ 0.25.0-lotus.10) when it arrives — "connection was
good", "3 reconnects", "connection was poor for 4 min". Nothing is
stored or sent; the summary is one postMessage at hangup. Without the
fork summary the toast still shows the duration.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPmy3tPq869XDW4njjVaKA

src/app/plugins/call/CallEmbed.ts

@@ -49,6 +49,14 @@ export interface LotusCallParticipant {
   speakingWhileMuted?: boolean;
 }
 
+/** [Gitea #143] The fork's one-shot io.lotus.call_summary payload. */
+export interface LotusCallSummary {
+  durationMs: number;
+  reconnects: number;
+  poorMs: number;
+  verdict: 'good' | 'fair' | 'poor' | 'unknown';
+}
+
 export class CallEmbed {
   private mx: MatrixClient;
 
@@ -60,6 +68,12 @@ export class CallEmbed {
 
   public joined = false;
 
+  /** [Gitea #143] When the first JoinCall landed, for the hangup readout. */
+  public joinedAt: number | undefined;
+
+  /** [Gitea #143] The fork's end-of-call summary, once it arrives. */
+  public lastSummary: LotusCallSummary | undefined;
+
   // C-M4: set once dispose() has run so the hangup fallback timer can tell
   // whether the embed was already torn down by the normal Close/Hangup echo.
   public disposed = false;
@@ -390,6 +404,19 @@ export class CallEmbed {
         this.forkStateRequestListeners.forEach((l) => l());
       }),
     );
+    this.disposables.push(
+      this.listenAction('io.lotus.call_summary', (evt) => {
+        const data = (evt.detail as { data?: Partial<LotusCallSummary> } | undefined)?.data;
+        if (data && typeof data.durationMs === 'number') {
+          this.lastSummary = {
+            durationMs: data.durationMs,
+            reconnects: data.reconnects ?? 0,
+            poorMs: data.poorMs ?? 0,
+            verdict: data.verdict ?? 'unknown',
+          };
+        }
+      }),
+    );
     this.disposables.push(
       this.listenAction('io.lotus.call_state', (evt) => {
         const data = (evt.detail as { data?: { participants?: unknown } } | undefined)?.data;
@@ -537,6 +564,7 @@ export class CallEmbed {
       return;
     }
     this.joined = true;
+    this.joinedAt = Date.now();
     // EC ignores io.element.device_mute before join; re-apply desired state now that EC is live
     this.control.forceState(this.initialState);
   }