[JS IR] - Remove file lowering declarations from lowering phases

- rename fileToPurenessInitializers onto fileToInitializerPureness
- remove redundant check on top-level property

[JS IR] Rename initialis* to initializ* for consistency

[JS IR] Move propertyLazyInitialization property to context from configuration

[JS IR] Add test on lazy initialization properties order

[JS IR] Add multi module for lazy initialization of properties

[JS IR] Move tests onto js.translator

[JS IR] Rename fileToInitializerPureness according to context name

^KT-43222 fixed

js/js.translator/testData/box/propertyAccess/lazyInitialization.kt

@@ -0,0 +1,18 @@
+// IGNORE_BACKEND: JS
+// DONT_TARGET_EXACT_BACKEND: WASM
+// PROPERTY_LAZY_INITIALIZATION
+
+// FILE: A.kt
+
+val o = "O"
+
+// FILE: B.kt
+val ok = o + k
+
+// FILE: C.kt
+
+val k = "K"
+
+// FILE: main.kt
+
+fun box(): String = ok

js/js.translator/testData/box/propertyAccess/lazyInitializationOrder.kt

@@ -0,0 +1,36 @@
+// EXPECTED_REACHABLE_NODES: 1239
+// DONT_TARGET_EXACT_BACKEND: WASM
+// PROPERTY_LAZY_INITIALIZATION
+
+// FILE: A.kt
+
+val a = "A".let {
+    flag = !flag
+    if (flag) {
+        it
+    } else {
+        "!A"
+    }
+}
+
+val b = "B".let {
+    flag = !flag
+    if (!flag) {
+        it
+    } else {
+        "!B"
+    }
+}
+
+// FILE: B.kt
+var flag: Boolean = false
+
+// FILE: main.kt
+
+fun box(): String {
+    return if (
+        a == "A" && b == "B"
+    )
+        "OK"
+    else "a = $a; b = ${b}"
+}

js/js.translator/testData/box/propertyAccess/lazyInitializationPure.kt

@@ -0,0 +1,32 @@
+// IGNORE_BACKEND: JS
+// PROPERTY_LAZY_INITIALIZATION
+
+// FILE: A.kt
+
+val a = "A"
+
+// FILE: B.kt
+val b = "B".apply {}
+
+val c = b
+
+// FILE: C.kt
+val d = "D".apply {}
+
+val e = d
+
+// FILE: main.kt
+
+fun box(): String {
+    // Get only e to initialize all properties in file
+    e
+    return if (
+        js("a") === "A" &&
+        js("typeof b") == "undefined" &&
+        js("typeof c") == "undefined" &&
+        js("d") === "D" &&
+        js("e") === "D"
+    )
+        "OK"
+    else "a = ${js("a")}; typeof b = ${js("typeof b")}; typeof c = ${js("typeof c")}; d = ${js("d")}; e = ${js("e")}"
+}

js/js.translator/testData/box/propertyAccess/lazyInitializationSplitPerModule.kt

@@ -0,0 +1,22 @@
+// IGNORE_BACKEND: JS
+// DONT_TARGET_EXACT_BACKEND: WASM
+// SPLIT_PER_MODULE
+// PROPERTY_LAZY_INITIALIZATION
+
+// MODULE: lib1
+// FILE: A.kt
+val o = "O"
+
+// FILE: B.kt
+val okCandidate = o + k
+
+// FILE: C.kt
+val k = "K"
+
+// MODULE: lib2(lib1)
+// FILE: lib2.kt
+val ok = okCandidate
+
+// MODULE: main(lib1, lib2)
+// FILE: main.kt
+fun box(): String = ok