feat(agents): add agent naming functionality (#1922)

# What does this PR do?
Allow users to name an agent and use the name in telemetry instead of
relying on randomly generated agent_ids. This improves the developer
experience by making it easier to find specific agents in telemetry
logs.

Closes #1832

## Test Plan

- Added tests to verify the agent name is properly stored and retrieved
- Ran `uv run -- pytest -v
tests/integration/telemetry/test_telemetry.py::test_agent_name_filtering`
from the root of the project and made sure the tests pass
- Ran `uv run -- pytest -v
tests/integration/telemetry/test_telemetry.py::test_agent_query_spans`
to verify existing code without agent names still works correctly

## Use Example
```
agent = Agent(
    llama_stack_client, 
    model=text_model_id, 
    name="CustomerSupportAgent",  # New parameter
    instructions="You are a helpful customer support assistant"
)
session_id = agent.create_session(f"test-session-{uuid4()}")
```

## Implementation Notes
- Agent names are optional string parameters with no additional
validation
- Names are not required to be unique - multiple agents can have the
same name
- The agent_id remains the unique identifier for an agent

---------

Co-authored-by: raghotham <raghotham@gmail.com>

tests/integration/agents/test_agents.py

@@ -115,6 +115,70 @@ def test_agent_simple(llama_stack_client_with_mocked_inference, agent_config):
         assert "I can't" in logs_str
 
 
+def test_agent_name(llama_stack_client, text_model_id):
+    agent_name = f"test-agent-{uuid4()}"
+
+    try:
+        agent = Agent(
+            llama_stack_client,
+            model=text_model_id,
+            instructions="You are a helpful assistant",
+            name=agent_name,
+        )
+    except TypeError:
+        agent = Agent(
+            llama_stack_client,
+            model=text_model_id,
+            instructions="You are a helpful assistant",
+        )
+        return
+
+    session_id = agent.create_session(f"test-session-{uuid4()}")
+
+    agent.create_turn(
+        messages=[
+            {
+                "role": "user",
+                "content": "Give me a sentence that contains the word: hello",
+            }
+        ],
+        session_id=session_id,
+        stream=False,
+    )
+
+    all_spans = []
+    for span in llama_stack_client.telemetry.query_spans(
+        attribute_filters=[
+            {"key": "session_id", "op": "eq", "value": session_id},
+        ],
+        attributes_to_return=["input", "output", "agent_name", "agent_id", "session_id"],
+    ):
+        all_spans.append(span.attributes)
+
+    agent_name_spans = []
+    for span in llama_stack_client.telemetry.query_spans(
+        attribute_filters=[],
+        attributes_to_return=["agent_name"],
+    ):
+        if "agent_name" in span.attributes:
+            agent_name_spans.append(span.attributes)
+
+    agent_logs = []
+    for span in llama_stack_client.telemetry.query_spans(
+        attribute_filters=[
+            {"key": "agent_name", "op": "eq", "value": agent_name},
+        ],
+        attributes_to_return=["input", "output", "agent_name"],
+    ):
+        if "output" in span.attributes and span.attributes["output"] != "no shields":
+            agent_logs.append(span.attributes)
+
+    assert len(agent_logs) == 1
+    assert agent_logs[0]["agent_name"] == agent_name
+    assert "Give me a sentence that contains the word: hello" in agent_logs[0]["input"]
+    assert "hello" in agent_logs[0]["output"].lower()
+
+
 def test_tool_config(llama_stack_client_with_mocked_inference, agent_config):
     common_params = dict(
         model="meta-llama/Llama-3.2-3B-Instruct",