fix: avoid relaunching running tasks

Mutating tasks caused them to appear to be different than existing
executions, causing them to be relaunched even when an equivalent task
had already been started. Avoid mutating tasks that are not created
internally (as opposed to fetched from existing tasks) so that such
comparisons work as expected.

src/server/createProcessTask.ts

@@ -1,13 +1,13 @@
-import { ProcessExecution, Task, TaskScope } from 'vscode';
+import { ProcessExecution, Task, TaskRevealKind, TaskScope } from 'vscode';
 import type { EnvironmentVariables } from './EnvironmentVariables';
 
 export const createProcessTask = (
   binPath: string,
   args: string[],
   cwdPath: string | undefined,
   injectedEnv: EnvironmentVariables,
-) =>
-  new Task(
+) => {
+  const task = new Task(
     { type: 'story-explorer' },
     TaskScope.Workspace,
     'Storybook Server',
@@ -17,3 +17,12 @@ export const createProcessTask = (
       env: injectedEnv,
     }),
   );
+
+  task.isBackground = true;
+  task.detail = 'Storybook Development Server';
+  task.presentationOptions = {
+    reveal: TaskRevealKind.Silent,
+  };
+
+  return task;
+};

src/server/getOrCreateTask.ts

@@ -1,6 +1,6 @@
 import { isDeepStrictEqual } from 'util';
 import { firstValueFrom } from 'rxjs';
-import { TaskRevealKind, tasks } from 'vscode';
+import { tasks } from 'vscode';
 import { storybookConfigLocation } from '../config/storybookConfigLocation';
 import { serverInternalEnvironmentVariablesConfigSuffix } from '../constants/constants';
 import { logDebug } from '../log/log';
@@ -121,12 +121,6 @@ export const getOrCreateTask = async () => {
     return undefined;
   }
 
-  task.isBackground = true;
-  task.detail = 'Storybook Development Server';
-  task.presentationOptions = {
-    reveal: TaskRevealKind.Silent,
-  };
-
   const existingExecution = tasks.taskExecutions.find(
     (execution) =>
       isDeepStrictEqual(execution.task.definition, task.definition) &&