Implement measurements create/destroy and display existing readouts

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

config/locales/en.yml

@@ -13,6 +13,9 @@ en:
       quantity:
         description: Description
         name: Name
+      readout:
+        created_at: Recorded at
+        value: Value
       unit:
         base: Base unit
         description: Description
@@ -89,6 +92,15 @@ en:
       taken_at_html: Measurement taken at 
     index:
       new_measurement: Add measurement
+    readout:
+      destroy: Delete
+    create:
+      success:
+        one: Recorded 1 measurement.
+        other: Recorded %{count} measurements.
+      no_readouts: No readouts selected.
+    destroy:
+      success: Measurement deleted.
   quantities:
     navigation: Quantities
     no_items: There are no configured quantities. You can Add some or Import from defaults.