fix(ui): align compact channel row consumers

docs/superpowers/plans/2026-07-30-responsive-channel-epg-preview.md

@@ -245,7 +245,9 @@ Replace the current `max-width: 220px` action-hiding rule with:
 The end time is already hidden by the wider breakpoint. Channel name, current
 programme or placeholder, progress, drag affordance, and every enabled action
 remain available in EPG rows. The `.compact` branch deliberately preserves the
-existing radio/non-EPG degradation.
+existing non-EPG degradation; radio-only consumers without EPG opt into that
+branch through `showEpg=false`, rather than changing mixed-list height through
+`isRadio`.
 
 - [ ] **Step 4: Match skeleton degradation to the live row**
 

docs/superpowers/specs/2026-07-29-responsive-channel-epg-preview-design.md

@@ -54,8 +54,10 @@ loading content does not jump between incompatible layouts.
 and global channel lists. The contract therefore applies consistently wherever
 the host becomes narrow. This PR does not add provider-specific overrides.
 
-Radio rows and compact rows without EPG keep their existing behavior. The
-change does not add EPG data where a consumer currently disables it.
+Compact rows without EPG keep their existing behavior. Radio-only consumers
+that do not expose EPG mark their rows compact; `isRadio` alone never changes
+height inside a fixed-size mixed virtual list. The change does not add EPG data
+where a consumer currently disables it.
 
 ## Alternatives Considered