Create a separate change log file for developers, automate notifications

[seanbudd]

Is your feature request related to a problem? Please describe.

• The general change log and changes for developers have 2 entirely different audiences
• Many translators do not translate changes for developers
• Many users find the changes for developers noise in the change log
• Many developers find it hard to hunt for changes for devs in the change log
• NV Access has to manually notify translators via nvda-api whenever deprecations or breaking changes occur

Describe the solution you'd like

• A separate "Changes for developers" and "Changes" file
• Nice to have: an optional way for translators to translate this file
  • reconsider the developer guide when doing this Remove outdated translated developerGuide, or move to Crowdin (was: remove outdated files) #13333
• Nice to have: Use GitHub actions like Update devGuide for translating symbols, gestures, character descriptions #17590 to automated emails for file changes to the changes for developers
  • Create different alerts for changes to master, beta, and rc. This allows add-on devs to decide more easily when to start work (e.g. keep up with alphas, or see a summary of all the changes introduced in the first beta).
• Nice to have: Migrate all previous changes for developers to this file, including translated content

Describe alternatives you've considered

• A smarter diffing system for automating notifications - this is a much harder problem with just 1 file. To notify differences you'd have to identify the section in the markdown file, which at that point could be used to generate a separate changes for dev file

Additional context