Fix flaky Maestro E2E sign-in setup on iOS

The e2eSignInAlice button only mounts once the proxy is configured, which
previously relied solely on the proxy TextInput's onSubmitEditing handler
triggered via `pressKey: Enter`. Enter is unreliable on the iOS simulator,
so the sign-in buttons sometimes never appeared and flows failed with
"Element not found: e2eSignInAlice".

- TestCtrls.e2e.tsx: extract the proxy-configuration logic into a named
  onConfigureProxy function, still called by onSubmitEditing (Enter remains
  a fallback), and add a dedicated e2eConfigureProxy Pressable that is
  always rendered so setup can tap it deterministically.
- setupApp.yml: tap e2eConfigureProxy instead of pressing Enter, then guard
  with an extendedWaitUntil for e2eSignInAlice (60000ms) so the race becomes
  an explicit bounded wait shared by every flow reusing this setup.
- run-nightly-e2e.sh: add `--retries 2` to the maestro test invocation so a
  single flaky miss doesn't fail the whole nightly run.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Umqi3SMj5PvH2ZVxQYWCcx

.github/scripts/run-nightly-e2e.sh

@@ -159,6 +159,7 @@ phase "Running Maestro flows"
 set +e
 maestro test \
   --udid "$device_id" \
+  --retries 2 \
   --format JUNIT \
   --output "$artifact_dir/report.xml" \
   --config __e2e__/config.yml \

__e2e__/setupApp.yml

@@ -33,4 +33,9 @@ appId: xyz.blueskyweb.app
 - tapOn:
     id: e2eProxyHeaderInput
 - inputText: ${output.result}
-- pressKey: Enter
+- tapOn:
+    id: e2eConfigureProxy
+- extendedWaitUntil:
+    visible:
+      id: e2eSignInAlice
+    timeout: 60000

src/view/com/testing/TestCtrls.e2e.tsx

@@ -62,6 +62,13 @@ export function TestCtrls() {
     setShowLoggedOut(false)
   }
   const [proxyHeader, setProxyHeader] = useState('')
+  const onConfigureProxy = () => {
+    const header = `${proxyHeader}#bsky_appview`
+    BLUESKY_PROXY_HEADER.set(header)
+    agent.configureProxy(header as any)
+    hasConfiguredProxy = true
+    setIsProxyConfigured(true)
+  }
   return (
     <View style={{position: 'absolute', top: 100, right: 0, zIndex: 100}}>
       <TextInput
@@ -72,13 +79,13 @@ export function TestCtrls() {
         autoComplete="off"
         autoCorrect={false}
         autoCapitalize="none"
-        onSubmitEditing={() => {
-          const header = `${proxyHeader}#bsky_appview`
-          BLUESKY_PROXY_HEADER.set(header)
-          agent.configureProxy(header as any)
-          hasConfiguredProxy = true
-          setIsProxyConfigured(true)
-        }}
+        onSubmitEditing={onConfigureProxy}
+        style={BTN}
+      />
+      <Pressable
+        testID="e2eConfigureProxy"
+        onPress={onConfigureProxy}
+        accessibilityRole="button"
         style={BTN}
       />
       {isProxyConfigured && (