feat(gateway): expose context usage and warning events

src/daemon/services.ts

@@ -411,6 +411,37 @@ export function createGateway(deps: GatewayDeps): GatewayServer {
         }
       }
 
+      return results;
+    },
+    getContextUsage: () => {
+      const results: Array<{
+        sessionId: string;
+        budget: {
+          estimatedTokens: number;
+          contextWindow: number;
+          remainingTokens: number;
+          usagePct: number;
+          thresholdPct: number;
+          thresholdTokens: number;
+          shouldCompact: boolean;
+        };
+      }> = [];
+
+      const sessionBridge = gateway.getSessionBridge();
+      for (const entry of sessionBridge.getAllContextUsage()) {
+        results.push(entry);
+      }
+
+      const channelAgents = getChannelAgents();
+      if (channelAgents) {
+        for (const [sessionId, { orchestrator }] of channelAgents) {
+          results.push({
+            sessionId,
+            budget: orchestrator.getContextBudget(),
+          });
+        }
+      }
+
       return results;
     },
   });