feat: Add Serper.dev search support to SearchToolkit

[gaivrt]

Description

This PR adds support for Serper.dev as a search engine option within the SearchToolkit.

Key changes include:

• Feature: Implemented search_serper method in camel/toolkits/search_toolkit.py following strict naming conventions (<toolkit_prefix>_<action>_<resource>).
• Documentation: Updated docs/reference/camel.toolkits.search_toolkit.md and docs/mintlify/reference/camel.toolkits.search_toolkit.mdx with detailed API documentation, strictly following docstring guidelines (using :obj: for defaults).
• Testing: Added comprehensive unit tests in test/toolkits/test_search_functions.py covering success and error scenarios.
• Examples: Updated examples/toolkits/search_toolkit.py to include a working example of search_serper with real output demonstration.
• Compliance: Ensured no sensitive keys are leaked, used logger instead of print (where applicable in library code), and avoided abbreviations in variable names.

Checklist

Go over all the following points, and put an x in all the boxes that apply.

• I have read the CONTRIBUTION guide (required)
• I have linked this PR to an issue using the Development section on the right sidebar or by adding Fixes #issue-number in the PR description (required)
• I have checked if any dependencies need to be added or updated in pyproject.toml and uv lock (No new dependencies, uses requests)
• I have updated the tests accordingly (required for a bug fix or a new feature)
• I have updated the documentation if needed
• I have added examples if this is a new feature

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on this repository.

Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Note

Other AI code review bot(s) detected

CodeRabbit has detected other AI code review bot(s) in this pull request and will avoid duplicating their findings in the review comments. This may lead to a less comprehensive review.

✨ Finishing touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[Copilot]

Copilot reviewed 5 out of 5 changed files in this pull request and generated 4 comments.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[fengju0213]

LGTM thanks @gaivrt !