[Swift Export] initial infrastructure for Swift IR

New modules 'sir', 'sir-passes', and 'sir-analysis-api' were added under
'native:swift' for creating and manipulating Swift IR elements.

* `sir` contains the implementation of Swift IR.
* `sir-analysis-api` contains translation from Analysis API to SIR.
* `sir-passses` contains transformation passes.

This groundwork will allow to progress with the Swift IR.

native/swift/sir/build.gradle.kts

@@ -0,0 +1,17 @@
+plugins {
+    kotlin("jvm")
+}
+
+description = "Swift Intermediate Representation"
+
+dependencies {
+    compileOnly(kotlinStdlib())
+
+    testImplementation(libs.junit4)
+    testImplementation(projectTests(":compiler:tests-common"))
+}
+
+sourceSets {
+    "main" { projectDefault() }
+    "test" { projectDefault() }
+}