frontend: Obsidian-style record graph + pop-out dialog + records list

The record graph was a cramped React Flow box wedged inside a sheet
section. Redesign it Obsidian-style — round nodes with the label
underneath, a soft glow, and a hover-focus that highlights a node plus
its neighbours while dimming the rest.

Move it out of the inline section: the sheet now shows an "Open graph"
button (closes the sheet, opens the graph in a large dialog) and a
clickable list of the patient's records (problems + visits); clicking a
record opens a detail dialog.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/lib/i18n/locales/en/translation.json

@@ -1111,8 +1111,20 @@
     },
     "graph": {
       "title": "Record graph",
-      "hint": "How this patient's problems and visits connect. Drag nodes; scroll to pan.",
-      "empty": "Not enough record data to graph yet."
+      "hint": "Hover a node to focus its connections. Scroll to pan, pinch to zoom.",
+      "empty": "Not enough record data to graph yet.",
+      "open": "Open graph",
+      "close": "Close",
+      "kind": {
+        "problem": "Problem",
+        "visit": "Visit"
+      },
+      "fields": {
+        "since": "Since",
+        "date": "Date",
+        "provider": "Provider",
+        "summary": "Summary"
+      }
     },
     "appointments": {
       "title": "Appointments",