Disable reckon plugin when used in Git worktree (#6331)

Author: TimoPtr

settings.gradle.kts

@@ -18,25 +18,33 @@ pluginManagement {
     }
 }
 
+// Reckon plugin doesn't work in git worktrees (JGit doesn't handle worktree .git files).
+// Detect worktrees (.git is a file, not a directory) and skip reckon in that case.
+val isWorktree = settings.settingsDir.resolve(".git").isFile
+
 plugins {
     // So we can't reach the libs.plugins.* aliases from here so we need to declare them the old way...
-    id("org.ajoberstar.reckon.settings").version("1.0.1")
+    id("org.ajoberstar.reckon.settings").version("1.0.1").apply(false)
 }
 
-reckon {
-    val isCiBuild = providers.environmentVariable("CI").isPresent
+if (!isWorktree) {
+    apply(plugin = "org.ajoberstar.reckon.settings")
+
+    extensions.configure<org.ajoberstar.reckon.gradle.ReckonExtension>("reckon") {
+        val isCiBuild = providers.environmentVariable("CI").isPresent
 
-    setDefaultInferredScope("patch")
-    if (!isCiBuild) {
-        // Use a snapshot version scheme with Reckon when not running in CI, which allows caching to
-        // improve performance. Background: https://github.com/home-assistant/android/issues/5220.
-        snapshots()
-    } else {
-        stages("beta", "final")
+        setDefaultInferredScope("patch")
+        if (!isCiBuild) {
+            // Use a snapshot version scheme with Reckon when not running in CI, which allows caching to
+            // improve performance. Background: https://github.com/home-assistant/android/issues/5220.
+            snapshots()
+        } else {
+            stages("beta", "final")
+        }
+        setScopeCalc { java.util.Optional.of(org.ajoberstar.reckon.core.Scope.PATCH) }
+        setStageCalc(calcStageFromProp())
+        setTagWriter { it.toString() }
     }
-    setScopeCalc { java.util.Optional.of(org.ajoberstar.reckon.core.Scope.PATCH) }
-    setStageCalc(calcStageFromProp())
-    setTagWriter { it.toString() }
 }
 
 dependencyResolutionManagement {