Cover remaining branches in api-env-switcher: unknown env, missing DOM elements

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/js/api-env-switcher.test.js

@@ -72,4 +72,37 @@ describe('initApiEnvSwitcher', () => {
 
         expect(document.getElementById('env-base-url').textContent).toContain('/api/live')
     })
+
+    it('handles unknown env gracefully', () => {
+        document.body.innerHTML = `
+            <div id="env-switcher">
+                <button data-env="unknown" class="env-btn">Unknown</button>
+            </div>
+            <div data-host="https://test.com">
+                <p id="env-base-url">original</p>
+            </div>
+            <p id="env-description">original desc</p>
+        `
+        initApiEnvSwitcher()
+
+        document.querySelector('[data-env="unknown"]').click()
+
+        expect(document.getElementById('env-base-url').textContent).toBe('original')
+        expect(document.getElementById('env-description').textContent).toBe('original desc')
+    })
+
+    it('works without base-url and description elements', () => {
+        document.body.innerHTML = `
+            <div id="env-switcher">
+                <button data-env="sandbox" class="env-btn">Sandbox</button>
+                <button data-env="live" class="env-btn">Live</button>
+            </div>
+            <div data-host="https://test.com"></div>
+            <span class="api-env-prefix">/api/sandbox</span>
+        `
+        initApiEnvSwitcher()
+
+        expect(() => document.querySelector('[data-env="live"]').click()).not.toThrow()
+        expect(document.querySelector('.api-env-prefix').textContent).toBe('/api/live')
+    })
 })