fix(FN-915): use getFusionDir() for agent storage location

- Add getFusionDir() method to TaskStore for resolving agent database path
- Update in-process-runtime to use getFusionDir() instead of hardcoded path
- Update dashboard routes AgentStore initialization to use getFusionDir()
- Add changeset for published package patch bump

packages/engine/src/runtimes/in-process-runtime.test.ts

@@ -13,6 +13,7 @@ vi.mock("@fusion/core", async () => {
     TaskStore: vi.fn().mockImplementation(function(this: TaskStore, rootDir: string) {
       const self = this as unknown as Record<string, unknown>;
       self.getRootDir = () => rootDir;
+      self.getFusionDir = () => rootDir + "/.fusion";
       self.init = vi.fn().mockResolvedValue(undefined);
       self.listTasks = vi.fn().mockResolvedValue([]);
       self.getSettings = vi.fn().mockResolvedValue({});

packages/engine/src/runtimes/in-process-runtime.ts

@@ -208,7 +208,7 @@ export class InProcessRuntime
       // 6. Initialize AgentStore and HeartbeatMonitor
       try {
         const { AgentStore: AgentStoreClass } = await import("@fusion/core");
-        this.agentStore = new AgentStoreClass({ rootDir: this.taskStore.getRootDir() });
+        this.agentStore = new AgentStoreClass({ rootDir: this.taskStore.getFusionDir() });
         await this.agentStore.init();
 
         this.heartbeatMonitor = new HeartbeatMonitor({