fix: return user-facing error when session reset after compaction failure

Previously, when auto-compaction failed due to context overflow, the system
would reset the session and silently continue the execution loop without
sending any response to the user. This made it appear as if messages were
being ignored.

This change ensures users receive a clear error message explaining that
the context limit was exceeded and the conversation has been reset,
consistent with how role ordering conflicts are already handled.

Fixes the silent failure case where message + compaction exceeds context limits.

src/auto-reply/reply/agent-runner-execution.ts

@@ -397,7 +397,12 @@ export async function runAgentTurnWithFallback(params: {
         (await params.resetSessionAfterCompactionFailure(embeddedError.message))
       ) {
         didResetAfterCompactionFailure = true;
-        continue;
+        return {
+          kind: "final",
+          payload: {
+            text: "⚠️ Context limit exceeded. I've reset our conversation to start fresh - please try again.",
+          },
+        };
       }
       if (embeddedError?.kind === "role_ordering") {
         const didReset = await params.resetSessionAfterRoleOrderingConflict(embeddedError.message);
@@ -427,7 +432,12 @@ export async function runAgentTurnWithFallback(params: {
         (await params.resetSessionAfterCompactionFailure(message))
       ) {
         didResetAfterCompactionFailure = true;
-        continue;
+        return {
+          kind: "final",
+          payload: {
+            text: "⚠️ Context limit exceeded during compaction. I've reset our conversation to start fresh - please try again.",
+          },
+        };
       }
       if (isRoleOrderingError) {
         const didReset = await params.resetSessionAfterRoleOrderingConflict(message);