feat: tab shell, home/onboarding UI, settings and keyboard polish

Introduce MainTabView with history and Liquid Glass dock; refresh home and
onboarding layouts; unify accent green and provider localization; refine
settings/API rows; redesign keyboard mic and flanking controls; set Utility
iPhone-only targets and Flow session reliability fixes.

OSGKeyboardShared/Utilities/ProviderDisplayName.swift

@@ -0,0 +1,15 @@
+// ProviderDisplayName.swift
+// OSGKeyboard · Shared
+//
+// Locale-aware provider labels for settings and status hints.
+
+import Foundation
+
+public enum ProviderDisplayName {
+    public static func name(for providerId: String) -> String {
+        let key = "provider.\(providerId)"
+        let localized = NSLocalizedString(key, comment: "")
+        if localized != key { return localized }
+        return LLMProvider.provider(id: providerId).name
+    }
+}