fix(server): include actual error details in DaemonRpcError messages

The catch-all handler was replacing real error messages with "Request
failed", and DaemonRpcError only showed the error string without
requestType or code context.

packages/server/src/client/daemon-client.ts

@@ -328,7 +328,10 @@ class DaemonRpcError extends Error {
   readonly code?: string
 
   constructor(params: { requestId: string; error: string; requestType?: string; code?: string }) {
-    super(params.error)
+    const parts = [params.error]
+    if (params.requestType) parts.push(`requestType=${params.requestType}`)
+    if (params.code) parts.push(`code=${params.code}`)
+    super(parts.join(' '))
     this.name = 'DaemonRpcError'
     this.requestId = params.requestId
     this.requestType = params.requestType

packages/server/src/server/session.ts

@@ -1723,7 +1723,7 @@ export class Session {
             payload: {
               requestId,
               requestType: msg.type,
-              error: 'Request failed',
+              error: `Request failed: ${err.message}`,
               code: 'handler_error',
             },
           })