chore: officially migrate to submodule (#4502)

* remove apps/core and apps/fern

* fix precommit

* add submodule updates in workflows

* submodule

* remove core tests

* update core revision

* Add submodules: true to all GitHub workflows

- Ensure all workflows can access git submodules
- Add submodules support to deployment, test, and CI workflows
- Fix YAML syntax issues in workflow files

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

* remove core-lint

* upgrade core with latest main of oss

---------

Co-authored-by: Claude <noreply@anthropic.com>

examples/docs/tools.py

@@ -1,110 +0,0 @@
-from letta_client import CreateBlock, Letta, MessageCreate
-from letta_client.types import TerminalToolRule
-
-"""
-Make sure you run the Letta server before running this example.
-```
-letta server
-```
-"""
-
-client = Letta(base_url="http://localhost:8283")
-
-# define a function with a docstring
-def roll_d20() -> str:
-    """
-    Simulate the roll of a 20-sided die (d20).
-
-    This function generates a random integer between 1 and 20, inclusive,
-    which represents the outcome of a single roll of a d20.
-
-    Returns:
-        int: A random integer between 1 and 20, representing the die roll.
-
-    Example:
-        >>> roll_d20()
-        15  # This is an example output and may vary each time the function is called.
-    """
-    import random
-
-    dice_role_outcome = random.randint(1, 20)
-    output_string = f"You rolled a {dice_role_outcome}"
-    return output_string
-
-
-# create a tool from the function
-tool = client.tools.upsert_from_function(func=roll_d20)
-print(f"Created tool with name {tool.name}")
-
-# create a new agent
-agent_state = client.agents.create(
-    memory_blocks=[
-        CreateBlock(
-            label="human",
-            value="Name: Sarah",
-        ),
-    ],
-    # set automatic defaults for LLM/embedding config
-    model="openai/gpt-4o-mini",
-    embedding="openai/text-embedding-3-small",
-    # create the agent with an additional tool
-    tool_ids=[tool.id],
-    tool_rules=[
-        # exit after roll_d20 is called
-        TerminalToolRule(tool_name=tool.name),
-        # exit after send_message is called (default behavior)
-        TerminalToolRule(tool_name="send_message"),
-    ]
-)
-print(f"Created agent with name {agent_state.name} with tools {[t.name for t in agent_state.tools]}")
-
-# Message an agent
-response = client.agents.messages.create(
-    agent_id=agent_state.id, 
-    messages=[
-        MessageCreate(
-            role="user",
-            content="roll a dice",
-        )
-    ],
-)
-print("Usage", response.usage)
-print("Agent messages", response.messages)
-
-# remove a tool from the agent
-client.agents.tools.detach(agent_id=agent_state.id, tool_id=tool.id)
-
-# add a tool to the agent
-client.agents.tools.attach(agent_id=agent_state.id, tool_id=tool.id)
-
-client.agents.delete(agent_id=agent_state.id)
-
-# create an agent with only a subset of default tools
-send_message_tool = [t for t in client.tools.list() if t.name == "send_message"][0]
-agent_state = client.agents.create(
-    memory_blocks=[
-        CreateBlock(
-            label="human",
-            value="username: sarah",
-        ),
-    ],
-    model="openai/gpt-4o-mini",
-    embedding="openai/text-embedding-3-small",
-    include_base_tools=False, 
-    tool_ids=[tool.id, send_message_tool.id],
-)
-
-# message the agent to search archival memory (will be unable to do so)
-client.agents.messages.create(
-    agent_id=agent_state.id,
-    messages=[
-        MessageCreate(
-            role="user",
-            content="search your archival memory",
-        )
-    ],
-)
-print("Usage", response.usage)
-print("Agent messages", response.messages)
-
-client.agents.delete(agent_id=agent_state.id)