Release v5.1.3: Fix PostToolUse hook field name bug

Bug Fix:
- Changed tool_output to tool_response throughout PostToolUse hook chain
- PostToolUse events provide tool_response field, not tool_output
- Updated save-hook.ts to send tool_response
- Updated worker-service.ts endpoint to accept tool_response
- Updated worker-service-v2.ts for consistency
- Updated worker-types.ts interfaces (PendingMessage, ObservationData)
- Updated SessionManager.ts message queue
- Updated SDKAgent.ts observation prompt builder

Impact: Fixes observation capture for PostToolUse events. Previous version was sending undefined for tool responses, causing incomplete observations.

Files changed:
- src/hooks/save-hook.ts (interface + destructuring + fetch body)
- src/services/worker-service.ts (ObservationMessage interface + handler + SDK prompt)
- src/services/worker-service-v2.ts (handler)
- src/services/worker-types.ts (PendingMessage + ObservationData interfaces)
- src/services/worker/SessionManager.ts (queue push)
- src/services/worker/SDKAgent.ts (observation prompt)
- plugin/scripts/*.js (rebuilt)
- Version bumped to 5.1.3 (patch)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/services/worker-service.ts

@@ -73,7 +73,7 @@ interface ObservationMessage {
   type: 'observation';
   tool_name: string;
   tool_input: string;
-  tool_output: string;
+  tool_response: string;
   prompt_number: number;
 }
 
@@ -753,11 +753,11 @@ class WorkerService {
 
   /**
    * POST /sessions/:sessionDbId/observations
-   * Body: { tool_name, tool_input, tool_output, prompt_number }
+   * Body: { tool_name, tool_input, tool_response, prompt_number }
    */
   private handleObservation(req: Request, res: Response): void {
     const sessionDbId = parseInt(req.params.sessionDbId, 10);
-    const { tool_name, tool_input, tool_output, prompt_number } = req.body;
+    const { tool_name, tool_input, tool_response, prompt_number } = req.body;
 
     const session = this.getOrCreateSession(sessionDbId);
     const toolStr = logger.formatTool(tool_name, tool_input);
@@ -771,7 +771,7 @@ class WorkerService {
       type: 'observation',
       tool_name,
       tool_input,
-      tool_output,
+      tool_response,
       prompt_number
     });
 
@@ -977,7 +977,7 @@ class WorkerService {
             id: 0,
             tool_name: message.tool_name,
             tool_input: message.tool_input,
-            tool_output: message.tool_output,
+            tool_output: message.tool_response,
             created_at_epoch: Date.now()
           });