feat: Add local_target variable and tests

tests/files/basic.plan

@@ -0,0 +1,2 @@
+sources=('file:/home/user')
+targets=('file:/var/backup')

tests/files/multiple_file_targets.plan

@@ -0,0 +1,7 @@
+sources=('file:/home/user')
+targets=(
+    'file:///home/backups'
+    'file:/var/backup'
+    'file:/backups'
+    's3://bucket'
+)