revert: restore the "Site Planner" sheet title (#6581)

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

core/resources/src/commonMain/composeResources/values/strings.xml

@@ -1584,7 +1584,7 @@
     <string name="signal">Signal</string>
     <string name="signal_quality">Signal Quality</string>
     <!-- SITE -->
-    <string name="site_planner">Estimate Coverage</string>
+    <string name="site_planner">Site Planner</string>
     <string name="site_planner_antenna_gain_dbi">Antenna gain (dBi)</string>
     <string name="site_planner_antenna_height_meters">Antenna height (m)</string>
     <string name="site_planner_color_scale">Color palette</string>