feat(api): include icon in app information response

[da-okazaki]

Summary

Add a icon to {api}/v1/info.

Screenshots

Before

{
    "name": "sample chat app",
    "description": "sample chat app description",
    "tags": [
        "tag_1",
        "tag_2"
    ]

}

After

{
    "name": "chat app 1",
    "description": "chat app 1 description",
    "tags": [
        "tag_1",
        "tag_2"
    ],
    "icon_type": "emoji",
    "icon": "😀",
    "icon_background": "#FF0000"
}

Checklist

[!IMPORTANT]
Please review the checklist below before submitting your pull request.

• [ ] This change requires a documentation update, included: Dify Document
• [x] I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• [ ] I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• [ ] I've updated the documentation accordingly.
• [x] I ran dev/reformat(backend) and cd web && npx lint-staged(frontend) to appease the lint gods

[kurokobo]

Hi, how about updating the corresponding documentation if you're going to change the API response? Refer to: https://github.com/langgenius/dify/pull/11269

[crazywoola]

Please fix the lint as well.

[da-okazaki]

@crazywoola Fixes made to lint.

[da-okazaki]

@kurokobo Documentation will be handled by the following users in a separate PR. We are developing a product using Didify and would like to use the functionality as soon as possible.

https://github.com/rikeda71

[fujita-h]

When icon_type is image, icon is the ID (UUID) of the image file. How can this be used?