fix(menubar): force status bar redraw and lift subprocess QoS

Two independent causes for the stuck-label / only-refreshes-on-click
behaviour, both fixed here.

1. NSStatusItem button defers the status bar paint for accessory apps
   that are not foreground, so after refreshStatusButton sets the new
   attributed title the menu bar visually froze until the user opened
   the popover (which triggers NSApp.activate and a forced redraw
   cycle). Explicit needsDisplay + display() forces the paint every
   cycle.

2. The codeburn subprocess inherited the accessory app's default QoS,
   which macOS background-throttles. That could stretch a sub-1-second
   parse into tens of seconds on large corpora and overrun the 15s
   refresh cadence. Set .userInitiated so the CLI runs at the same
   priority it does from a user-interactive terminal.

mac/Sources/CodeBurnMenubar/Security/CodeburnCLI.swift

@@ -41,6 +41,11 @@ enum CodeburnCLI {
         // `env --` treats everything following as argv, not VAR=val pairs -- guards against an
         // argument accidentally resembling an env assignment.
         process.arguments = ["--"] + baseArgv() + subcommand
+        // The menubar runs as an accessory app with no foreground window, and macOS
+        // background-throttles accessory apps and their children. Without this lift the
+        // codeburn subprocess parses 5-10x slower than the same command run from a
+        // user-interactive terminal, which starves the 15s refresh cadence on large corpora.
+        process.qualityOfService = .userInitiated
         return process
     }