fix(claude-code-mixin): sentence case panel titles

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

Author: ishanjainn

claude-code-mixin/dashboards/claude-code-overview.json

@@ -1631,7 +1631,7 @@
           "refId": "B"
         }
       ],
-      "title": "Session Outcome",
+      "title": "Session outcome",
       "type": "piechart"
     },
     {
@@ -1713,7 +1713,7 @@
           "refId": "A"
         }
       ],
-      "title": "Commits / Session",
+      "title": "Commits / session",
       "type": "stat"
     },
     {
@@ -4736,4 +4736,4 @@
   "uid": "claude-code-overview",
   "version": 4,
   "weekStart": ""
-}
+}