Feature - Add SearchApi Tool

[SebastjanPrachovskij]

Description

We have integrated a new tool - SearchApi. Right now we added Google, Google Jobs, Google News, and YouTube Transcripts engines.

• This is our initial PR; we want to improve it later based on the users' feedback. Most likely changes will affect how the final results string is being built.
• Feel free to assign @SebastjanPrachovskij as a main reviewer for any SearchApi-related searches. We will be glad to help and support dify development.

Fixes # (issue)

Type of Change

Please delete options that are not relevant.

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

How Has This Been Tested?

• By creating a workflow in the studio.

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