fix: add payload validation guard in onWebhook handler

src/worker.ts

@@ -729,15 +729,16 @@ const plugin = definePlugin({
 		};
 
 		const { caseNumber, oldStatus, newStatus, companyId } = payload;
+
+		if (!caseNumber || !newStatus || !companyId) {
+			pluginCtx.logger.warn("onWebhook: malformed payload", { caseNumber, newStatus, companyId });
+			return;
+		}
+
 		pluginCtx.logger.info(`Webhook: case ${caseNumber} ${oldStatus} → ${newStatus}`, {
 			companyId,
 		});
 
-		if (!companyId) {
-			pluginCtx.logger.warn("onWebhook: missing companyId in payload", { caseNumber });
-			return;
-		}
-
 		// Find the Paperclip issue linked to this case number by scanning plugin state.
 		// State stores: issue.id → case_number (scopeKind=issue, stateKey=legal-case-number)
 		const issues = await pluginCtx.issues.list({ companyId });