Close [BS-2751](https://linear.app/affine-design/issue/BS-2751).
### What Changed?
- Do not send AI gql request when chat-panel is not open.
- When the chat-panel width is greater than 540px, adjust the padding to 24px.
- Optimize the display and hide logic of scroll to end button.
Issue：Close [BS-2150](https://linear.app/affine-design/issue/BS-2150/图片-filterprocessing-二级菜单时而不出现)
In the AI image menu (based on floating-ui):
- **Floating element**: Submenu items (e.g., "image filter/image processing")
- **Reference element**: Menu item
- **Positioning strategy**: `fixed`
- **Issue**: Specifying the `container` parameter caused the floating element (submenu) to be mounted to the reference element (menu item), leading to incorrect position calculations when floating-ui updated.
```jsx
<menu-item>
<submenu-item style={{ position: 'fixed' }}/>
</menu-item>
```
- **Fix**: Remove the `container` configuration and mount the `fixed`-positioned floating element to the `body` instead.
The primary purpose of this PR appears to be:
1. Simplifying the change notification API by removing the redundant value parameter from callbacks
2. Improving the reactive system's handling of specialized types (Text and Boxed) in flat data
3. Adding better test coverage for text handling in the flat data model
This PR implements a significant refactoring of the embed block services across multiple components (Figma, GitHub, Loom, and YouTube) in the BlockSuite codebase. Here are the key changes:
1. **Architecture Change**:
- Moves from a dynamic registration pattern to a more declarative configuration approach
- Replaces `EmbedOptionProvider.registerEmbedBlockOptions()` calls with a new `EmbedOptionConfig` factory function
2. **Service Refactoring**:
- For each embed block type (Figma, GitHub, Loom, YouTube):
- Separates configuration from service logic
- Creates new `EmbedBlockOptionConfig` constants using the new `EmbedOptionConfig` factory
- Removes the `mounted()` lifecycle hook from services where it was only used for registration
3. **Core Changes**:
- In `embed-option-service.ts`:
- Introduces new `EmbedOptionConfigIdentifier` for dependency injection
- Adds `EmbedOptionConfig` factory function for creating embed configurations
- Updates `EmbedOptionService` constructor to automatically register configurations
- Modifies DI setup to include `StdIdentifier` dependency
4. **Spec Updates**:
- Updates all block specs to include the new configuration objects
- Maintains existing functionality while using the new pattern
The main benefit of this refactoring is:
- More declarative configuration approach
- Better separation of concerns
- Reduced runtime registration code
- More predictable initialization of embed options
