Migrate from .NET MAUI to Expo + Convex

Complete rewrite of Scry using TypeScript stack:

- Expo/React Native with Expo Router (file-based routing)
- Convex backend (serverless functions + real-time database)
- Adaptive camera system (expo-camera in Expo Go, Vision Camera in production)
- React Native Skia + fast-opencv for image processing
- GDPR-compliant auth setup with Zitadel OIDC (pending configuration)

Key features:
- Card recognition pipeline ported to TypeScript
- Perceptual hashing (192-bit color pHash)
- CLAHE preprocessing for lighting normalization
- Local SQLite cache with Convex sync
- Collection management with offline support

Removes all .NET/MAUI code (src/, test/, tools/).

💘 Generated with Crush

Assisted-by: Claude Opus 4.5 via Crush <crush@charm.land>

lib/recognition/imageLoader.ts

@@ -0,0 +1,95 @@
+/**
+ * Image loader utilities for React Native.
+ * Loads images from file paths and returns pixel data for recognition.
+ */
+
+import * as ImageManipulator from "expo-image-manipulator";
+import { Platform } from "react-native";
+
+export interface LoadedImage {
+  pixels: Uint8Array;
+  width: number;
+  height: number;
+}
+
+/**
+ * Load image from a file path and return RGBA pixel data.
+ * Uses expo-image-manipulator to resize the image to a manageable size first.
+ *
+ * Note: expo-image-manipulator doesn't directly provide pixel data.
+ * We need to use a canvas (web) or Skia (native) to decode pixels.
+ * For now, this provides the resized image URI for the Skia-based decoder.
+ */
+export async function loadImageForRecognition(
+  uri: string,
+  targetWidth: number = 480, // Reasonable size for processing
+  targetHeight: number = 640
+): Promise<{ uri: string; width: number; height: number }> {
+  // Normalize the URI for the platform
+  const normalizedUri =
+    Platform.OS === "android" && !uri.startsWith("file://")
+      ? `file://${uri}`
+      : uri;
+
+  // Resize the image for faster processing
+  const result = await ImageManipulator.manipulateAsync(
+    normalizedUri,
+    [
+      {
+        resize: {
+          width: targetWidth,
+          height: targetHeight,
+        },
+      },
+    ],
+    {
+      compress: 1,
+      format: ImageManipulator.SaveFormat.PNG,
+    }
+  );
+
+  return {
+    uri: result.uri,
+    width: result.width,
+    height: result.height,
+  };
+}
+
+/**
+ * Load image and get base64 data.
+ * Useful for passing to native modules or Skia.
+ */
+export async function loadImageAsBase64(
+  uri: string,
+  targetWidth: number = 480,
+  targetHeight: number = 640
+): Promise<{ base64: string; width: number; height: number }> {
+  // Normalize the URI
+  const normalizedUri =
+    Platform.OS === "android" && !uri.startsWith("file://")
+      ? `file://${uri}`
+      : uri;
+
+  const result = await ImageManipulator.manipulateAsync(
+    normalizedUri,
+    [
+      {
+        resize: {
+          width: targetWidth,
+          height: targetHeight,
+        },
+      },
+    ],
+    {
+      compress: 1,
+      format: ImageManipulator.SaveFormat.PNG,
+      base64: true,
+    }
+  );
+
+  return {
+    base64: result.base64 || "",
+    width: result.width,
+    height: result.height,
+  };
+}