fix: increase max crash key value length

[nornagon]

Description of Change

This allows storing more complex data in the crash values, and will enable Sentry's reporter to switch away from their custom uploader.

This will waste memory for smaller crash keys, but most apps use only a small number of crash keys, so the excess won't be significant. In future, we can optimize this further by either separating crash keys into various classes by length, or expanding the API to allow the user to specify the maximum length of the key, or some other system.

Checklist

• PR description included and stakeholders cc'd
• npm test passes
• tests are changed or added
• relevant documentation is changed or added
• PR title follows semantic commit guidelines
• PR release notes describe the change in a way relevant to app developers, and are capitalized, punctuated, and past tense.
• This is NOT A BREAKING CHANGE. Breaking changes may not be merged to master until 11-x-y is branched.

Release Notes

Notes: Increased maximum length for crash keys from 127B to 20KB.

[release-clerk]

Release Notes Persisted

Increased maximum length for crash keys from 127B to 20KB.

[trop]

I was unable to backport this PR to "10-x-y" cleanly;
you will need to perform this backport manually.

[trop]

I was unable to backport this PR to "9-x-y" cleanly;
you will need to perform this backport manually.

[trop]

@nornagon has manually backported this PR to "10-x-y", please check out #24853

[trop]

@nornagon has manually backported this PR to "9-x-y", please check out #24854