fix: remove unnecessary user lookup in agent API calls (#17934)

# Use workspace.OwnerUsername instead of fetching the owner

This PR optimizes the agent API by using the `workspace.OwnerUsername` field directly instead of making an additional database query to fetch the owner's username. The change removes the need to call `GetUserByID` in the manifest API and workspace agent RPC endpoints.

An issue arose when the agent token was scoped without access to user data (`api_key_scope = "no_user_data"`), causing the agent to fail to fetch the manifest due to an RBAC issue.

Change-Id: I3b6e7581134e2374b364ee059e3b18ece3d98b41
Signed-off-by: Thomas Kosiewski <tk@coder.com>

coderd/workspaceagents_test.go

@@ -439,25 +439,55 @@ func TestWorkspaceAgentConnectRPC(t *testing.T) {
 	t.Run("Connect", func(t *testing.T) {
 		t.Parallel()
 
-		client, db := coderdtest.NewWithDatabase(t, nil)
-		user := coderdtest.CreateFirstUser(t, client)
-		r := dbfake.WorkspaceBuild(t, db, database.WorkspaceTable{
-			OrganizationID: user.OrganizationID,
-			OwnerID:        user.UserID,
-		}).WithAgent().Do()
-		_ = agenttest.New(t, client.URL, r.AgentToken)
-		resources := coderdtest.AwaitWorkspaceAgents(t, client, r.Workspace.ID)
+		for _, tc := range []struct {
+			name        string
+			apiKeyScope rbac.ScopeName
+		}{
+			{
+				name:        "empty (backwards compat)",
+				apiKeyScope: "",
+			},
+			{
+				name:        "all",
+				apiKeyScope: rbac.ScopeAll,
+			},
+			{
+				name:        "no_user_data",
+				apiKeyScope: rbac.ScopeNoUserData,
+			},
+			{
+				name:        "application_connect",
+				apiKeyScope: rbac.ScopeApplicationConnect,
+			},
+		} {
+			t.Run(tc.name, func(t *testing.T) {
+				client, db := coderdtest.NewWithDatabase(t, nil)
+				user := coderdtest.CreateFirstUser(t, client)
+				r := dbfake.WorkspaceBuild(t, db, database.WorkspaceTable{
+					OrganizationID: user.OrganizationID,
+					OwnerID:        user.UserID,
+				}).WithAgent(func(agents []*proto.Agent) []*proto.Agent {
+					for _, agent := range agents {
+						agent.ApiKeyScope = string(tc.apiKeyScope)
+					}
 
-		ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
-		defer cancel()
+					return agents
+				}).Do()
+				_ = agenttest.New(t, client.URL, r.AgentToken)
+				resources := coderdtest.NewWorkspaceAgentWaiter(t, client, r.Workspace.ID).AgentNames([]string{}).Wait()
 
-		conn, err := workspacesdk.New(client).
-			DialAgent(ctx, resources[0].Agents[0].ID, nil)
-		require.NoError(t, err)
-		defer func() {
-			_ = conn.Close()
-		}()
-		conn.AwaitReachable(ctx)
+				ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+				defer cancel()
+
+				conn, err := workspacesdk.New(client).
+					DialAgent(ctx, resources[0].Agents[0].ID, nil)
+				require.NoError(t, err)
+				defer func() {
+					_ = conn.Close()
+				}()
+				conn.AwaitReachable(ctx)
+			})
+		}
 	})
 
 	t.Run("FailNonLatestBuild", func(t *testing.T) {