Convert to building a universal Mac app (#6302)

.taskfiles/desktop.yml

@@ -1,7 +1,12 @@
 version: '3'
 
 vars:
-  JLINK_MODULES: "java.base,java.compiler,java.desktop,java.instrument,java.logging,java.management,java.naming,java.net.http,java.prefs,java.rmi,java.scripting,java.security.jgss,java.security.sasl,java.sql,java.transaction.xa,java.xml,java.xml.crypto,jdk.crypto.ec,jdk.crypto.cryptoki,jdk.unsupported"
+  # Single source of truth for the jlink module list (also read by
+  # frontend/scripts/build-universal-mac-jre.sh during CI). The desktop
+  # taskfile runs with dir: frontend (see Taskfile.yml), so this path
+  # is relative to that directory.
+  JLINK_MODULES:
+    sh: tr -d '\n' < src-tauri/jlink-modules.txt
 
 tasks:
   prepare:
@@ -96,7 +101,7 @@ tasks:
         jlink
         --add-modules {{.JLINK_MODULES}}
         --strip-debug
-        --compress=2
+        --compress=zip-6
         --no-header-files
         --no-man-pages
         --output src-tauri/runtime/jre
@@ -107,3 +112,18 @@ tasks:
     desc: "Remove JLink runtime and bundled JARs"
     cmds:
       - rm -rf src-tauri/libs src-tauri/runtime
+
+  # macOS-only. Replaces jlink:runtime's single-arch JRE with a universal
+  # (arm64 + x86_64) one for the universal Tauri shell. Runs the x86_64
+  # jlink under Rosetta on Apple Silicon, so it is opt-in and not part of
+  # the default desktop:build flow. Requires AARCH64_JAVA_HOME and
+  # X64_JAVA_HOME to point at matching JDK installations with jmods/.
+  jlink:universal-mac:
+    desc: "Create universal (arm64+x86_64) JRE for the macOS Tauri build"
+    deps: [jlink:jar]
+    platforms: [darwin]
+    env:
+      JLINK_MODULES: "{{.JLINK_MODULES}}"
+      OUTPUT_DIR: src-tauri/runtime/jre
+    cmds:
+      - scripts/build-universal-mac-jre.sh