🎉 feat(flow_style.py): add FlowStyle model and its CRUD classes

The FlowStyle model is added to the project, which represents the style of a flow. It has a color and an emoji field, and a foreign key to the Flow model. The CRUD classes are also added to the file, which are FlowStyleCreate, FlowStyleRead, and FlowStyleUpdate. These classes are used to create, read, and update FlowStyle instances respectively.

src/backend/langflow/database/models/flow_style.py

@@ -0,0 +1,33 @@
+# Path: src/backend/langflow/database/models/flowstyle.py
+
+from langflow.database.models.base import SQLModelSerializable
+from sqlmodel import Field, Relationship
+from uuid import UUID, uuid4
+from typing import TYPE_CHECKING, Optional
+
+if TYPE_CHECKING:
+    from langflow.database.models.flow import Flow
+
+
+class FlowStyleBase(SQLModelSerializable):
+    color: str
+    emoji: str
+    flow_id: UUID = Field(default=None, foreign_key="flow.id")
+
+
+class FlowStyle(FlowStyleBase, table=True):
+    id: UUID = Field(default_factory=uuid4, primary_key=True, unique=True)
+    flow: "Flow" = Relationship(back_populates="style")
+
+
+class FlowStyleUpdate(SQLModelSerializable):
+    color: Optional[str] = None
+    emoji: Optional[str] = None
+
+
+class FlowStyleCreate(FlowStyleBase):
+    pass
+
+
+class FlowStyleRead(FlowStyleBase):
+    id: UUID