feat(core): better cause data extraction

[ha1fstack]

Before submitting a pull request, please take a look at our
Contributing guidelines and verify:

• If you've added code that should be tested, please add tests.
• Ensure your code lints and the test suite passes (yarn lint) & (yarn test).

---

closes #15142

When using ExtraErrorDataIntegration, error.cause serializes with .toString() which is not very informative considering the purpose of the integration.

This PR improves error.cause handling in ExtraErrorDataIntegration by recursing the _extractErrorData for a single cause depth. To match the outer structure and provide more information the cause object is wrapped with [name].

The .toString() serialized data is gone now but if we are using LinkedErrorsIntegration the string message will still be visible.

Since these changes are useful enough, I think more detailed specifications (like cause recursion) could be addressed by future PRs - open to suggestions.

Before:

// error.cause was serialized as: "SyntaxError: bar" { TypeError: { cause: "SyntaxError: bar" // Just toString() output } }

After:

// error.cause now includes full error data extraction { TypeError: { cause: { SyntaxError: { baz: 42, foo: "aaaa...a...", } } } }

[s1gr1d]

This sounds like a good idea. Thanks for submitting this