Updated API stability policy (#19599)
### Link to issue number:
n/a
### Summary of the issue:
Updated developer guide to make NV Access's policy on API breaking
changes more transparent and explicit.
### Description of user facing changes:
n/a
### Description of developer facing changes:
Documentation - developer guide.
### Description of development approach:
n/a
### Testing strategy:
n/a
### Known issues with pull request:
n/a
### Code Review Checklist:
- [x] Documentation:
- Change log entry
- User Documentation
- Developer / Technical Documentation
- Context sensitive help for GUI changes
- [x] Testing:
- Unit tests
- System (end to end) tests
- Manual testing
- [x] UX of all users considered:
- Speech
- Braille
- Low Vision
- Different web browsers
- Localization in other languages / culture than English
- [x] API is compatible with existing add-ons.
- [x] Security precautions taken.
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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Sean Budd <sean@nvaccess.org>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
