feat(issues): Use title from React caused errors

[armenzg]

Starting with React 19, errors can include a cause error. Instead of using the generic Error title, we can use the title from the cause error, thus, making each issue unique.

This design shows what the Issue Stream looks like now vs after this change:

[eps1lon]

Why is this specific to React hydration errors? Error.prototype.cause is standardized nowadays so it seems to me it shouldn't be special cased for React.

[armenzg]

Why is this specific to React hydration errors? Error.prototype.cause is standardized nowadays so it seems to me it shouldn't be special cased for React.

It would take more time to get the data to determine the extent of the impact of the change. I am currently investigating getting the data.

[codecov]

Codecov Report

Attention: Patch coverage is 85.29412% with 5 lines in your changes missing coverage. Please review.

Project coverage is 78.05%. Comparing base (8a09244) to head (a2a76d1).
Report is 22 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #72593       +/-   ##
===========================================
+ Coverage   55.17%   78.05%   +22.88%     
===========================================
  Files        6582     6596       +14     
  Lines      293476   293958      +482     
  Branches    50641    50705       +64     
===========================================
+ Hits       161911   229440    +67529     
+ Misses     127476    58261    -69215     
- Partials     4089     6257     +2168     

Files	Coverage Δ
src/sentry/eventtypes/error.py	96.42% <100.00%> (+16.79%)	⬆️
src/sentry/grouping/strategies/newstyle.py	97.15% <95.00%> (+53.67%)	⬆️
src/sentry/interfaces/exception.py	76.51% <42.85%> (+28.95%)	⬆️

... and 2053 files with indirect coverage changes

[eps1lon]

Makes sense. React uses cause in other places as well e.g. for "There was an error during concurrent rendering but React was able to recover [...]".

[lobsterkatie]

@eps1lon - It's not always clear whether we want to use cause. For example, in our codebase we attach generic API errors as the cause of various more specific errors, and the latter are what we want to use for titling and grouping.

For lots more on this, see #64088 and the various issues it links to.