fix(api): fix alembic offline mode (#19285)

Alembic's offline mode generates SQL from SQLAlchemy migration operations,
providing developers with a clear view of database schema changes without
requiring an active database connection.

However, some migration versions (specifically bbadea11becb and d7999dfa4aae)
were performing database schema introspection, which fails in offline mode
since it requires an actual database connection.

This commit:
- Adds offline mode support by detecting context.is_offline_mode()
- Skips introspection steps when in offline mode
- Adds warning messages in SQL output to inform users that assumptions were made
- Prompts users to review the generated SQL for accuracy

These changes ensure migrations work consistently in both online and offline modes.

Close #19284.

api/models/tools.py

@@ -1,6 +1,6 @@
 import json
 from datetime import datetime
-from typing import Any, Optional, cast
+from typing import Any, cast
 
 import sqlalchemy as sa
 from deprecated import deprecated
@@ -304,8 +304,11 @@ class DeprecatedPublishedAppTool(Base):
         db.UniqueConstraint("app_id", "user_id", name="unique_published_app_tool"),
     )
 
+    id = db.Column(StringUUID, server_default=db.text("uuid_generate_v4()"))
     # id of the app
     app_id = db.Column(StringUUID, ForeignKey("apps.id"), nullable=False)
+
+    user_id: Mapped[str] = db.Column(StringUUID, nullable=False)
     # who published this tool
     description = db.Column(db.Text, nullable=False)
     # llm_description of the tool, for LLM
@@ -325,34 +328,3 @@ class DeprecatedPublishedAppTool(Base):
     @property
     def description_i18n(self) -> I18nObject:
         return I18nObject(**json.loads(self.description))
-
-    id = db.Column(StringUUID, server_default=db.text("uuid_generate_v4()"))
-    user_id: Mapped[str] = db.Column(StringUUID, nullable=False)
-    tenant_id: Mapped[str] = db.Column(StringUUID, nullable=False)
-    conversation_id: Mapped[Optional[str]] = db.Column(StringUUID, nullable=True)
-    file_key: Mapped[str] = db.Column(db.String(255), nullable=False)
-    mimetype: Mapped[str] = db.Column(db.String(255), nullable=False)
-    original_url: Mapped[Optional[str]] = db.Column(db.String(2048), nullable=True)
-    name: Mapped[str] = mapped_column(default="")
-    size: Mapped[int] = mapped_column(default=-1)
-
-    def __init__(
-        self,
-        *,
-        user_id: str,
-        tenant_id: str,
-        conversation_id: Optional[str] = None,
-        file_key: str,
-        mimetype: str,
-        original_url: Optional[str] = None,
-        name: str,
-        size: int,
-    ):
-        self.user_id = user_id
-        self.tenant_id = tenant_id
-        self.conversation_id = conversation_id
-        self.file_key = file_key
-        self.mimetype = mimetype
-        self.original_url = original_url
-        self.name = name
-        self.size = size