Return task when creating a task

[ahopkins]

Closes #3090

When creating a task from the Sanic app, we return the Asyncio task so that we can call the result later.

[Copilot]

Pull request overview

This PR enables users to retrieve the result of tasks created via app.add_task() by adding a return statement to the internal task wrapper. Previously, task results were discarded even though the Task object itself was returned.

Key changes:

• Modified _prep_task() internal wrapper to return the awaited task result
• Added comprehensive tests for both direct coroutine and callable task patterns

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
sanic/app.py	Added return statement in the _prep_task method's internal do() coroutine to preserve and propagate task results
tests/test_tasks.py	Added two new test cases verifying that task results can be retrieved via both await task and task.result() for coroutines and callables

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.893%. Comparing base (002c8c2) to head (3e4f05d).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #3114   +/-   ##
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  Coverage   87.893%   87.893%           
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  Files          105       105           
  Lines         8078      8078           
  Branches      1281      1281           
=========================================
  Hits          7100      7100           
  Misses         671       671           
  Partials       307       307           

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