fix: add sessionAccountId mapping and use in before_message_write

- Add sessionAccountId Map to track sessionKey -> accountId
- Save accountId in before_model_resolve when resolving accountId
- Use sessionChannelId/sessionAccountId fallback in before_message_write

plugin/index.ts

@@ -27,6 +27,7 @@ const sessionDecision = new Map<string, DecisionRecord>();
 const sessionAllowed = new Map<string, boolean>(); // Track if session was allowed to speak (true) or forced no-reply (false)
 const sessionInjected = new Set<string>(); // Track which sessions have already injected the end marker
 const sessionChannelId = new Map<string, string>(); // Track sessionKey -> channelId mapping
+const sessionAccountId = new Map<string, string>(); // Track sessionKey -> accountId mapping
 const MAX_SESSION_DECISIONS = 2000;
 const DECISION_TTL_MS = 5 * 60 * 1000;
 function buildEndMarkerInstruction(endSymbols: string[], isGroupChat: boolean): string {
@@ -637,10 +638,13 @@ export default {
           }
           // Allowed to speak - record this session as allowed
           sessionAllowed.set(key, true);
-          // Also save channelId for this session
+          // Also save channelId and accountId for this session
           if (derived.channelId) {
             sessionChannelId.set(key, derived.channelId);
           }
+          if (accountId) {
+            sessionAccountId.set(key, accountId);
+          }
         }
       }
 
@@ -836,6 +840,14 @@ export default {
           accountId = String(deliveryContext.accountId);
         }
 
+        // Fallback: get from session mapping
+        if (!channelId && key) {
+          channelId = sessionChannelId.get(key);
+        }
+        if (!accountId && key) {
+          accountId = sessionAccountId.get(key);
+        }
+
         // Fallback: get content from event.message.content
         if (!content && (event as Record<string, unknown>).message) {
           const msg = (event as Record<string, unknown>).message as Record<string, unknown>;