feat(chat): add tool utils to delegate execution

[ctlai95]

Problem

Tool APIs are not consistent.

Solution

Create a tool util wrapper class around tools to delegate validation, execution, and previews of tools.

So now to use the tools we can do something like:

const tool = ToolUtils.tryFromToolUse(toolUse)

ToolUtils.validate(tool)
ToolUtils.requiresAcceptance(tool)
ToolUtils.queueDescription(tool)
ToolUtils.invoke(tool)

---

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[github-actions]

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[ctlai95]

/retryBuilds

[mr-lee]

what's the intent of this class?

[ctlai95]

The idea was to have this be a helper class to interact with all the tools and to sort of enforce a common interface (requiresAcceptance, invoke, etc) so that we don't need to keep writing if-else or switch statements just to handle tools. This is how the CLI does it as well

[justinmk3]

Seems like a case where class-based inheritance would fit.

[mr-lee]

I feel like this code is not extensible for when we support MCP-based tools. Can we revisit this after the prototype?

[ctlai95]

Sure, I need to think about how MCP will work here. Happy to revisit later

[mr-lee]

I know you didn't change this - but I feel like we should refactor this to have a cleaner interface. Having a giant if/else block doesn't seem like the right solution.

[ctlai95]

Yeah that was the goal of this PR to have the common interface across all the tools (I just didn't get to refactoring this part yet since @laileni-aws will be integrating his UI changes here)

[mr-lee]

I'm approving to unblock - but I also think we need to refactor here.

[jpinkney-aws]

is there a reason why this was changed? if it needs to be changed can you make it on master

[ctlai95]

I accidentally committed this change to this branch in a previous commit. Here I'm reverting it back to what it is in master.

On another note, my vscode keeps trying to run watch using yarn instead of npm even in master. I noticed this happening for others as well so I'll make this change in master