Implement Handler mobile app (React Native + Expo iOS)

Build the committed 2a interactive prototype from Handler Mobile.dc.html as
a real Expo app: six wired screens (Fleet, Agent detail, Answer, Spawn, Log,
Settings) with the exact state logic ported from the design's renderVals().

- Port Leeworks tokens (colors light/dark, typography, spacing, radii,
  shadows) to typed RN values in src/theme.
- Reimplement the design-system components used by the screens (Button,
  Badge, Icon, Switch, Select, TextField, segmented control, chip, tab bar).
- Shared store mirrors the prototype's single-screen navigation and the
  Waiting -> Running flip when agt-7a1d is answered.
- Real OS status bar / home indicator (safe-area insets) replace the mock
  phone chrome; dark mode follows system appearance.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PdF2hHVQ4UUBFPtpeMQ81o

app/src/components/Chip.tsx

@@ -0,0 +1,55 @@
+import React from "react";
+import { Pressable, StyleSheet, Text } from "react-native";
+import { fonts, radius } from "../theme/tokens";
+import { useTheme } from "../theme/useTheme";
+
+/**
+ * Pill chip used for both the answer quick-replies and the log filters.
+ * Ported from the `chip()` style helper in the DC script.
+ */
+export function Chip({
+  label,
+  selected,
+  onPress,
+}: {
+  label: string;
+  selected: boolean;
+  onPress: () => void;
+}) {
+  const { colors } = useTheme();
+  return (
+    <Pressable
+      onPress={onPress}
+      style={[
+        styles.chip,
+        {
+          backgroundColor: selected ? colors.interactive : colors.surfacePage,
+          borderColor: selected ? colors.borderStrong : colors.borderDefault,
+        },
+      ]}
+    >
+      <Text
+        style={[
+          styles.label,
+          { color: selected ? "#ffffff" : colors.textBody },
+        ]}
+      >
+        {label}
+      </Text>
+    </Pressable>
+  );
+}
+
+const styles = StyleSheet.create({
+  chip: {
+    paddingVertical: 8,
+    paddingHorizontal: 14,
+    borderRadius: radius.pill,
+    borderWidth: 1,
+  },
+  label: {
+    fontFamily: fonts.bodyMedium,
+    fontSize: 13,
+    lineHeight: 13,
+  },
+});