feat(ios): comprehensive iPhone+iPad UX polish — refined-native design system

Freeze a shared design system (DesignSystem/{Tokens,Typography,StatusStyle,
Primitives}.swift): indigo #7C8CFF accent (root .tint), semantic status colors,
2-4-8-12-16-20-24 spacing + sm8/md12/lg16 radii scale, SF Mono tabular numbers,
reduce-motion-gated animations, haptics, reusable StatusBadge/TelemetryChip/Card/
SectionHeader/DSButtonStyle/ContinueLastBanner. Every changed view consumes tokens
— no hardcoded colors/spacing.

Applied across all surfaces (visual only — zero behavior/logic change, all suites
green): session list rows + status system (shape+color, not color-alone) +
telemetry chips + thumbnail placeholders; terminal gate card (≥44pt approve/reject)
+ keybar + reconnect + quick-reply + digest + SwiftTerm accent theme; pairing hero
+ warning tiers + Projects cards + Timeline/Diff; nav chrome + iPad split placeholder
+ privacy shade + motion. Chinese gate copy. UX finding fixed: timeline class colors
now via DS.Palette (+timelineTool/timelineUser tokens).

Design review 8.5/10. Verified: iPhone 16 290 + iPad Pro 11 290 tests green;
packages + integration green; consistency audit ~clean; zero changes under
ios/Packages, src/, public/.

ios/App/WebTerm/DesignSystem/Typography.swift

@@ -0,0 +1,60 @@
+import SwiftUI
+
+/// # Typography — the SF type ramp (FROZEN public surface)
+///
+/// All font choices come from `DS.Typography`. The ramp maps to Apple's
+/// semantic text styles so everything scales with Dynamic Type (the a11y
+/// audit's "keep it scalable" point). Numbers/dimensions/cost/`cols×rows`/
+/// timestamps use `mono(_:)` — SF Mono with tabular figures — so columns line
+/// up and digits don't jitter as values change (matches the existing
+/// `TelemetryChips`/`Timeline` convention, now centralized).
+extension DS {
+    enum Typography {
+
+        // ── Proportional ramp (Dynamic-Type scaling, semantic styles) ───────
+
+        /// Screen hero title.
+        static let largeTitle = Font.largeTitle
+        /// Section / prominent title.
+        static let title = Font.title2
+        /// Emphasis / card heading.
+        static let headline = Font.headline
+        /// Default body text.
+        static let body = Font.body
+        /// Slightly smaller body (secondary actions).
+        static let callout = Font.callout
+        /// Meta / caption text.
+        static let caption = Font.caption
+
+        // ── Monospaced (numbers, dimensions, timestamps) ────────────────────
+
+        /// SF Mono + tabular figures at the given text style (default `.body`).
+        /// Use for anything numeric that must align or not jump: `cols×rows`,
+        /// device/client counts, `$cost`, context %, relative timestamps.
+        static func mono(_ style: Font.TextStyle = .body) -> Font {
+            .system(style, design: .monospaced).monospacedDigit()
+        }
+
+        /// The canonical meta-number font: caption-sized mono + tabular.
+        static let metaMono = mono(.caption)
+    }
+}
+
+// MARK: - MetaText style
+
+/// Secondary + monospaced-tabular styling for a row's numeric meta line
+/// ("N 台设备在看 · 161×50"). Apply via `.dsMetaText()`.
+struct MetaText: ViewModifier {
+    func body(content: Content) -> some View {
+        content
+            .font(DS.Typography.metaMono)
+            .foregroundStyle(DS.Palette.textSecondary)
+    }
+}
+
+extension View {
+    /// Style a meta/number line as secondary monospaced-tabular text.
+    func dsMetaText() -> some View {
+        modifier(MetaText())
+    }
+}