feat(chat): Adding the grep search tool and file search tool

[grl-wang]

1. Implemented the grep search tool using https://github.com/microsoft/vscode-ripgrep.
2. The grepped result show as clickable file path.
3. Implemented the file search tool.
3. The tool currently is disable in current pr, once grepSearch tool tested, will update the tool_index.json to enable this tool.

Problem

Solution

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• Treat all work as PUBLIC. Private feature/x branches will not be squash-merged at release time.
• Your code changes must meet the guidelines in CONTRIBUTING.md.
• License: I confirm that my contribution is made under the terms of the Apache 2.0 license.

[github-actions]

• This pull request implements a feat or fix, so it must include a changelog entry (unless the fix is for an unreleased feature). Review the changelog guidelines.
  • Note: beta or "experiment" features that have active users should announce fixes in the changelog.
  • If this is not a feature or fix, use an appropriate type from the title guidelines. For example, telemetry-only changes should use the telemetry type.