♻️ Refactor backend bundle build process.

Now the final artifact is a single, compiled uberjar.
It considerably improves startup speed.

backend/build.clj

@@ -0,0 +1,37 @@
+(ns build
+  (:refer-clojure :exclude [compile])
+  (:require
+   [clojure.tools.build.api :as b]
+   [clojure.java.io]))
+
+(def class-dir "target/classes")
+(def basis (b/create-basis {:project "deps.edn"}))
+(def jar-file "target/penpot.jar")
+
+(defn clean [_]
+  (b/delete {:path "target"}))
+
+(defn jar [_]
+  (b/copy-dir
+   {:src-dirs ["src" "resources"]
+    :target-dir class-dir})
+
+  (b/compile-clj
+   {:basis basis
+    :src-dirs ["src"]
+    :class-dir class-dir})
+
+  (b/uber
+   {:class-dir class-dir
+    :uber-file jar-file
+    :main 'clojure.main
+    :basis basis}))
+
+(defn compile [_]
+  (b/javac
+   {:src-dirs ["dev/java"]
+    :class-dir class-dir
+    :basis basis
+    :exclude [#"com.google.*" #"goog.*"]
+    :javac-opts ["-source" "11" "-target" "11"]}))
+