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>

tests/test_tool_schema_parsing_files/all_python_complex.py

@@ -1,57 +0,0 @@
-from typing import List, Optional
-
-from pydantic import BaseModel, Field
-
-
-class ArgsSchema(BaseModel):
-    order_number: int = Field(
-        ...,
-        description="The order number to check on.",
-    )
-    customer_name: str = Field(
-        ...,
-        description="The customer name to check on.",
-    )
-    related_tickets: List[str] = Field(
-        ...,
-        description="A list of related ticket numbers.",
-    )
-    related_ticket_reasons: dict = Field(
-        ...,
-        description="A dictionary of reasons for each related ticket.",
-    )
-    severity: float = Field(
-        ...,
-        description="The severity of the order.",
-    )
-    metadata: Optional[dict] = Field(
-        None,
-        description="Optional metadata about the order.",
-    )
-
-
-def check_order_status(
-    order_number: int,
-    customer_name: str,
-    related_tickets: List[str],
-    related_ticket_reasons: dict,
-    severity: float,
-    metadata: Optional[dict],
-):
-    """
-    Check the status for an order number (integer value).
-
-    Args:
-        order_number (int): The order number to check on.
-        customer_name (str): The name of the customer who placed the order.
-        related_tickets (List[str]): A list of ticket numbers related to the order.
-        related_ticket_reasons (dict): A dictionary of reasons for the related tickets.
-        severity (float): The severity of the request (between 0 and 1).
-        metadata (Optional[dict]): Additional metadata about the order.
-
-    Returns:
-        str: The status of the order (e.g. cancelled, refunded, processed, processing, shipping).
-    """
-    # TODO replace this with a real query to a database
-    dummy_message = f"Order {order_number} is currently processing."
-    return dummy_message