fix(test): add missing metrics and model fields to Footer test mock

useStatusLine hook accesses sessionStats.metrics.tools.totalCalls,
sessionStats.metrics.files.totalLinesAdded, and currentModel which
were missing from the mock UIState, causing a TypeError crash during
render and making 4 Footer tests fail in CI.

packages/cli/src/ui/components/Footer.test.tsx

@@ -34,7 +34,22 @@ const createMockUIState = (overrides: Partial<UIState> = {}): UIState =>
   ({
     sessionStats: {
       lastPromptTokenCount: 100,
+      sessionId: 'test-session',
+      metrics: {
+        models: {},
+        tools: {
+          totalCalls: 0,
+          totalSuccess: 0,
+          totalFail: 0,
+          totalDurationMs: 0,
+          totalDecisions: { accept: 0, reject: 0, modify: 0, auto_accept: 0 },
+          byName: {},
+        },
+        files: { totalLinesAdded: 0, totalLinesRemoved: 0 },
+      },
     },
+    currentModel: 'gemini-pro',
+    branchName: undefined,
     geminiMdFileCount: 0,
     contextFileNames: [],
     showToolDescriptions: false,