Added comprehensive tests for core components

[pankaj-bind]

Description

This pull request addresses the "Limited Test Coverage for Core Components" issue by introducing a comprehensive suite of unit and integration tests for the fasta2a library's core components.

[cite_start]Previously, the test suite only validated the agent card endpoint (/.well-known/agent.json) tests/test_applications.py, leaving critical components like
TaskManager
Broker
Storage
Worker
without any test coverage. This gap could allow bugs in the main task processing logic to go unnoticed.

Solution

To resolve this, I have added the following new test files:

• [cite_start]tests/test_storage.py: Adds unit tests for the InMemoryStorage class[cite: 1265]. These tests verify the functionality of submitting, loading, and updating tasks, as well as managing the conversation context.
• [cite_start]tests/test_broker.py: Tests the InMemoryBroker [cite: 1045] to ensure that task operations are correctly sent and received through its in-memory message stream.
• tests/test_task_manager.py: Introduces an integration test for the TaskManager that simulates the full, end-to-end lifecycle of a task. It uses a MockWorker to confirm that tasks are correctly submitted via the TaskManager, processed by a worker, and that their final state is accurately reflected in storage.

These tests are designed to be robust and handle the asynchronous nature of the library, preventing the race conditions and deadlocks encountered during development.

Value

• Increases Reliability
• Improves Maintainability
• Enhances Confidence

[izzymsft]

This looks good to me. Thanks @pankaj-bind for sending this in