Update getErrors (GetErrors / problems) tool (#394)

* Update getErrors (GetErrors / problems) tool

Update this tool so it can gather all errors.

* Updated model description so agent knows the tool can gather all errors
* Updated implementation such that if no URL is given, the tool returns all
errors.

* Update tool definition

Made the 'filePaths' argument optional, and updated description
to indicate how the argument should be used.

* Updates from review

* Made filePaths on IGetErrorParams optional, updated implementation of
invoke accordingly.
* Updated prepareInvoke to handle optional argument properly as
well.

* Tweaks

---------

Co-authored-by: Rob Lourens <roblourens@gmail.com>