Refactor backend to support interface-definition driven model resources

- Introduce a new model structure for managing interface definitions and model resources, enhancing the backend's capability to handle various service integrations.
- Update the Makefile to reflect changes in database seeding and resource management commands.
- Remove the deprecated credentials management routes and replace them with a unified model registry API.
- Modify existing routes and schemas to align with the new model structure, ensuring seamless integration with the frontend.
- Enhance database seeding scripts to populate new model resources and their configurations.
- Update README documentation to reflect the new architecture and usage instructions for model resources and interface definitions.

backend/db/session.py

@@ -6,9 +6,11 @@
 """
 
 from collections.abc import AsyncGenerator
+import json
 
 import config
 from db.models import Base
+from services.interface_catalog import INTERFACE_DEFINITIONS
 from sqlalchemy import text
 from sqlalchemy.ext.asyncio import (
     AsyncSession,
@@ -28,22 +30,26 @@ async def get_session() -> AsyncGenerator[AsyncSession, None]:
 async def init_db() -> None:
     async with engine.begin() as conn:
         await conn.run_sync(Base.metadata.create_all)
-        # MVP 兼容迁移:create_all 不会给已存在的表补列。
         await conn.execute(
             text(
-                "ALTER TABLE provider_credentials "
-                "ADD COLUMN IF NOT EXISTS voice VARCHAR(128) NOT NULL DEFAULT ''"
+                "ALTER TABLE interface_definitions "
+                "ALTER COLUMN field_schema TYPE JSONB USING field_schema::jsonb"
             )
         )
-        await conn.execute(
-            text(
-                "ALTER TABLE provider_credentials "
-                "ADD COLUMN IF NOT EXISTS speed DOUBLE PRECISION NOT NULL DEFAULT 1.0"
+        for definition in INTERFACE_DEFINITIONS:
+            await conn.execute(
+                text(
+                    "INSERT INTO interface_definitions "
+                    "(interface_type, name, capability, field_schema, enabled, version) "
+                    "VALUES (:interface_type, :name, :capability, CAST(:field_schema AS jsonb), TRUE, 1) "
+                    "ON CONFLICT (interface_type) DO UPDATE SET "
+                    "name = EXCLUDED.name, capability = EXCLUDED.capability, "
+                    "field_schema = EXCLUDED.field_schema, enabled = TRUE, updated_at = now()"
+                ),
+                {
+                    "interface_type": definition["interface_type"],
+                    "name": definition["name"],
+                    "capability": definition["capability"],
+                    "field_schema": json.dumps({"fields": definition["fields"]}),
+                },
             )
-        )
-        await conn.execute(
-            text(
-                "ALTER TABLE provider_credentials "
-                "ADD COLUMN IF NOT EXISTS language VARCHAR(32) NOT NULL DEFAULT ''"
-            )
-        )