build: format codebase imports using ruff linter (#1028)

# What does this PR do?

- Configured ruff linter to automatically fix import sorting issues.
- Set --exit-non-zero-on-fix to ensure non-zero exit code when fixes are
applied.
- Enabled the 'I' selection to focus on import-related linting rules.
- Ran the linter, and formatted all codebase imports accordingly.
- Removed the black dep from the "dev" group since we use ruff

Signed-off-by: Sébastien Han <seb@redhat.com>

[//]: # (If resolving an issue, uncomment and update the line below)
[//]: # (Closes #[issue-number])

## Test Plan
[Describe the tests you ran to verify your changes with result
summaries. *Provide clear instructions so the plan can be easily
re-executed.*]

[//]: # (## Documentation)
[//]: # (- [ ] Added a Changelog entry if the change is significant)

Signed-off-by: Sébastien Han <seb@redhat.com>

tests/client-sdk/agents/test_agents.py

@@ -13,12 +13,14 @@ from llama_stack_client.lib.agents.agent import Agent
 from llama_stack_client.lib.agents.client_tool import ClientTool
 from llama_stack_client.lib.agents.event_logger import EventLogger
 from llama_stack_client.types import ToolResponseMessage
-from llama_stack_client.types.shared_params.agent_config import AgentConfig, ToolConfig
 from llama_stack_client.types.agents.turn_create_params import Document as AgentDocument
 from llama_stack_client.types.memory_insert_params import Document
 from llama_stack_client.types.shared.completion_message import CompletionMessage
+from llama_stack_client.types.shared_params.agent_config import AgentConfig, ToolConfig
 from llama_stack_client.types.tool_def_param import Parameter
-from llama_stack.apis.agents.agents import AgentConfig as Server__AgentConfig, ToolChoice
+
+from llama_stack.apis.agents.agents import AgentConfig as Server__AgentConfig
+from llama_stack.apis.agents.agents import ToolChoice
 
 
 class TestClientTool(ClientTool):

tests/client-sdk/conftest.py

@@ -6,11 +6,11 @@
 import os
 
 import pytest
+from llama_stack_client import LlamaStackClient
+from report import Report
 
 from llama_stack import LlamaStackAsLibraryClient
 from llama_stack.providers.tests.env import get_env_or_fail
-from llama_stack_client import LlamaStackClient
-from report import Report
 
 
 def pytest_configure(config):

tests/client-sdk/report.py

@@ -22,15 +22,13 @@ from llama_models.sku_list import (
     llama3_instruct_models,
     safety_models,
 )
+from metadata import API_MAPS
+from pytest import CollectReport
+from termcolor import cprint
 
 from llama_stack.providers.datatypes import Api
 from llama_stack.providers.tests.env import get_env_or_fail
 
-from metadata import API_MAPS
-
-from pytest import CollectReport
-from termcolor import cprint
-
 
 def featured_models():
     models = [

tests/client-sdk/tool_runtime/test_rag_tool.py

@@ -7,7 +7,6 @@
 import random
 
 import pytest
-
 from llama_stack_client.types import Document