Add core functionality for mobile post scheduling app

Adds necessary dependencies including axios and react-native-calendars to pnpm-lock.yaml.

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artifacts/postiz-mobile/hooks/useColors.ts

@@ -0,0 +1,24 @@
+import { useColorScheme } from "react-native";
+
+import colors from "@/constants/colors";
+
+/**
+ * Returns the design tokens for the current color scheme.
+ *
+ * The returned object contains all color tokens for the active palette
+ * plus scheme-independent values like `radius`.
+ *
+ * Falls back to the light palette when no dark key is defined in
+ * constants/colors.ts (the scaffold ships light-only by default).
+ * When a sibling web artifact's dark tokens are synced into a `dark`
+ * key, this hook will automatically switch palettes based on the
+ * device's appearance setting.
+ */
+export function useColors() {
+  const scheme = useColorScheme();
+  const palette =
+    scheme === "dark" && "dark" in colors
+      ? (colors as Record<string, typeof colors.light>).dark
+      : colors.light;
+  return { ...palette, radius: colors.radius };
+}