Fix usage parsing to use "all models" weekly stat

The usage parser was matching the first "Current week" line it found,
which could be model-specific (e.g., Opus 4.5 only). Update both the
expect script and Swift parsing to specifically look for the
"Current week (all models)" line to get combined usage across all
models.

Author: StuartCameronCode

clive/UsageManager.swift

@@ -90,8 +90,8 @@ class UsageManager {
                     send "\\r"
                     exp_continue
                 }
-                -re "Current week.*\\n.*\\d+%" {
-                    # Got the data we need
+                -re "Current week \\(all models\\).*\\n.*\\d+%" {
+                    # Got the data we need (all models stat)
                 }
                 timeout {
                     exit 1
@@ -226,10 +226,11 @@ func parseUsageOutput(_ output: String) -> UsageInfo? {
         }
     }
 
-    if let lastWeeklyRange = output.range(of: "Current week", options: .backwards) {
-        let afterWeekly = output[lastWeeklyRange.upperBound...]
-        if let match = afterWeekly.range(of: #"\d+%"#, options: .regularExpression) {
-            weeklyPercent = String(afterWeekly[match])
+    // Look specifically for "Current week (all models)" to get the combined usage across all models
+    if let allModelsRange = output.range(of: "Current week (all models)", options: .backwards) {
+        let afterAllModels = output[allModelsRange.upperBound...]
+        if let match = afterAllModels.range(of: #"\d+%"#, options: .regularExpression) {
+            weeklyPercent = String(afterAllModels[match])
         }
     }