feat: instrument analysis

frontend/src/App.tsx

@@ -140,8 +140,15 @@ function NormalRoutes() {
   const location = useLocation()
   if (KEEP_ALIVE_PATHS.has(location.pathname)) return null
 
-  // On instrument paths the keep-alive layer renders the UI; this Routes just registers the tab
-  const isInstrument = /^\/instruments\/\w/.test(location.pathname)
+  // On instrument paths the keep-alive layer renders the UI; this Routes just registers the tab.
+  // Was `/^\/instruments\/\w/` (required a word char right after the slash) — encoded ids
+  // that start with a character encodeURIComponent escapes (^GSPC -> %5EGSPC) begin with
+  // "%", which isn't \w, so this evaluated false for that tab. isInstrument then picked
+  // 'flex-1 overflow-auto' instead of 'hidden' for this otherwise-empty div, and — since
+  // InstrumentKeepAlive's own div is ALSO flex-1 in the same flex column — the two split
+  // the available height roughly 50/50 instead of the instrument page getting all of it,
+  // which is exactly the "page only fills half the screen" symptom.
+  const isInstrument = location.pathname.startsWith('/instruments/')
 
   return (
     <div className={isInstrument ? 'hidden' : 'flex-1 overflow-auto'}>