feat: install app from remote

[perzeuss]

Description

I am building DifyShare, a platform to share Dify apps. To allow importing them with a button click from DifyShare, this PR introduces the ability to install apps from an url. This functionality can be used for other scenarios too.

Type of Change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

I tested it locally. To test it manually:

• Configure beta.difyshare.com as allowed host by adding this to the .env for the web app: APP_IMPORT_FROM_REMOTE_ALLOWED_HOSTS="beta.difyshare.com"
• Visit the Dify Studio (navigate to /apps)
• Add ?action=installApp&remoteInstallUrl=https://beta.difyshare.com/api/flow/663ffe78002cf37178fa/download to the URL
• Open the URL
  • A loading spinner should be rendered with a message in the users locale
  • The Chatflow from DifyShare should succeed and you see the workflow editor

Suggested Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• I ran dev/reformat(backend) and cd web && npx lint-staged(frontend) to appease the lint gods
• optional I have made corresponding changes to the documentation
• optional I have added tests that prove my fix is effective or that my feature works
• optional New and existing unit tests pass locally with my changes

[bowenliang123]

-1 for having DifyShare in the Dify code. DifyShare should not be treated as an official platform for Dify, especially from a community user prospective.

This PR integrates DifyShare into Dify, as a fact which probably violates the Terms of Service of DifyShare (https://difyshare.com/terms-of-service) itself. The Disclaimer part of the ToS of DifyShare is weak, only mentioning separate operations for Dify and DifyShare.

Also, this PR leads to a penetration consequence that all the Dify users over SaaS and community use DifyShare in some way, forcing it to follow the Acceptance of ToS of DifyShare.

[perzeuss]

Hello @bowenliang123, thank you for your feedback. I'll remove the DifyShare URL from the web/.env.example file.

[bowenliang123]

Btw, has Dify been registered as a registered trademark or listed as an unregistered trademark by law?