fix: apply CodeRabbit auto-fixes

Fixed 1 file(s) based on 2 unresolved review comments.

Co-authored-by: CodeRabbit <noreply@coderabbit.ai>

docs/SPORTS_UNIFICATION.md

@@ -265,10 +265,13 @@ migrate there.)
 ### B5 — adoption is safe by construction
 
 A plugin adopting core imports keeps its bundled copy and reaches it through the
-guarded import (see the Upgradability table above). On a core that ships the
+guarded import (see the Upgradability table above). On a core that doesn't ship
-module the plugin uses core code; on one that doesn't it falls back and behaves
+the module the plugin falls back and behaves exactly as it does today. That
-exactly as it does today. There is no version of this step that breaks a user,
+fallback compatibility is safe by construction. On a core that *does* ship the
-which is why it does not wait for B6's gate.
+module, correctness is not automatic — object-level and scroll-mode validation
+(building both classes and comparing, per the retrospective below) is required
+to prove full behavior. There is no version of this step that breaks a user *on
+an old core*, which is why it does not wait for B6's gate.
 
 The hockey scroll-display pilot is **already validated**: adopted against a core
 carrying 3.2.0, `scroll_display.py` went from 691 to 289 lines and all 16 harness