Added big dot (●) indicator for current session in modal (#3980)

Co-authored-by: opencode-agent[bot] <opencode-agent[bot]@users.noreply.github.com>
Co-authored-by: rekram1-node <rekram1-node@users.noreply.github.com>
Co-authored-by: Aiden Cline <aidenpcline@gmail.com>

packages/opencode/src/cli/cmd/tui/ui/dialog-select.tsx

@@ -273,6 +273,11 @@ function Option(props: {
   const { theme } = useTheme()
   return (
     <>
+      <Show when={props.current && !props.active}>
+        <text flexShrink={0} fg={theme.primary} marginRight={0.5}>
+          ●
+        </text>
+      </Show>
       <text
         flexGrow={1}
         fg={props.active ? theme.background : props.current ? theme.primary : theme.text}