xet-uploads: re-compile xet wasm with fix for compute_file_hash function (#1736)

Updates the wasm used by the xet upload portion of the library to
include latest fixes to compute_file_hash function to process large
files correctly.

Also update the build-xet-wasm.sh script to (either can be reverted just
comment below)
- work on macos (base64 command requires `-i` flag on macos)
- adds to the comment at the top of the `chunker_wasm_bg.wasm.base64.ts`
to include some information about when the file was created and with
what parameters.

WASM binary is 99KB

Author: assafvayner

packages/hub/scripts/build-xet-wasm.sh

@@ -222,15 +222,31 @@ if [[ -n "$OUTPUT_DIR" ]]; then
     log "Output copied to: $OUTPUT_DIR"
 fi
 
+# Detect operating system for base64 command compatibility
+OS=$(uname)
+if [[ "$OS" == "Darwin" ]]; then
+    BASE64_CMD="base64 -i"
+    log "Detected macOS - using base64 -i flag"
+else
+    BASE64_CMD="base64"
+    log "Detected Linux/Unix - using standard base64"
+fi
+
 # copy the generated hf_xet_thin_wasm_bg.js to the hub package and hf_xet_thin_wasm_bg.wasm to the hub package
 cp "$CLONE_DIR/$PACKAGE/pkg/hf_xet_thin_wasm_bg.js" "./src/vendor/xet-chunk/chunker_wasm_bg.js"
 cp "$CLONE_DIR/$PACKAGE/pkg/hf_xet_thin_wasm_bg.wasm.d.ts" "./src/vendor/xet-chunk/chunker_wasm_bg.wasm.d.ts"
-cat << 'EOF' > "./src/vendor/xet-chunk/chunker_wasm_bg.wasm.base64.ts"
+cat << EOF > "./src/vendor/xet-chunk/chunker_wasm_bg.wasm.base64.ts"
 // Generated by build-xet-wasm.sh
+// Repository: $REPO_URL
+// Branch: $BRANCH
+// Package: $PACKAGE
+// JS Target: $JS_TARGET
+// Build Date: $(date -u +"%Y-%m-%d %H:%M:%S UTC")
+
 export const wasmBase64 = atob(
-	`
+	\`
 EOF
-base64 "$CLONE_DIR/$PACKAGE/pkg/hf_xet_thin_wasm_bg.wasm" | fold -w 100 >> "./src/vendor/xet-chunk/chunker_wasm_bg.wasm.base64.ts"
+$BASE64_CMD "$CLONE_DIR/$PACKAGE/pkg/hf_xet_thin_wasm_bg.wasm" | fold -w 100 >> "./src/vendor/xet-chunk/chunker_wasm_bg.wasm.base64.ts"
 cat << 'EOF' >> "./src/vendor/xet-chunk/chunker_wasm_bg.wasm.base64.ts"
 `
 		.trim()