Codify breaking change guidelines (#13066)

* Codify breaking change guidelines

* feedback

* Rename title and add expectations section

* Update docs/src/apps/backwards-compatibility.md

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>

* Update docs/src/apps/backwards-compatibility.md

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>

* Update docs/src/apps/backwards-compatibility.md

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>

* Update docs/src/apps/backwards-compatibility.md

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>

* Update docs/src/apps/backwards-compatibility.md

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>

* Update docs/src/apps/backwards-compatibility.md

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>

* Update docs/src/apps/backwards-compatibility.md

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>

* Update backwards-compatibility.md

* Update docs/src/apps/backwards-compatibility.md

Co-authored-by: Trent Nelson <trent.a.b.nelson@gmail.com>

* Update docs/src/apps/backwards-compatibility.md

Co-authored-by: Trent Nelson <trent.a.b.nelson@gmail.com>

* Update docs/src/apps/backwards-compatibility.md

Co-authored-by: Trent Nelson <trent.a.b.nelson@gmail.com>

* Apply suggestions from code review

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>
Co-authored-by: Trent Nelson <trent.a.b.nelson@gmail.com>

* Specify rust crates and add deprecation process

* Promise semver for software releases

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>
Co-authored-by: Trent Nelson <trent.a.b.nelson@gmail.com>

docs/sidebars.js

@@ -71,6 +71,7 @@ module.exports = {
       "apps/javascript-api",
       "apps/builtins",
       "apps/sysvars",
+      "apps/backwards-compatibility",
     ],
     "Integrating": ["integrations/exchange"],
     "Validating": [