Replace double chip filters with segmented control + dropdown menu in ProgramsTab

Swap the two horizontal FilterChip scroll rows with a native segmented
Picker for body zone and a toolbar Menu for difficulty level. Fix zone
values to match Supabase enum (upper-body, lower-body, full-body).
Remove unused FilterChip struct.

tabatago-swift/TabataGo/Resources/Localizable.xcstrings

@@ -543,6 +543,9 @@
           }
         }
       }
+    },
+    "All" : {
+
     },
     "Any challenges?" : {