virtual/pentoo-sources: fix logic and document logic

virtual/pentoo-sources/pentoo-sources-1-r1.ebuild

@@ -0,0 +1,26 @@
+# Copyright 2026 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=9
+
+DESCRIPTION="Meta package for Pentoo kernel sources"
+SLOT="0"
+KEYWORDS="amd64 arm arm64 x86"
+IUSE="lts"
+
+# The logic flow:
+#  If we install virtual/pentoo-sources we want sys-kernel/pentoo-sources
+#  Maybe later that will include sys-kernel/pentoo-kernel when it exists
+#  If we have the lts use flag set, we have to have a sources installed with the lts flag set AND
+#  no sources installed without the lts flag set otherwise we might accidently build a non-lts kernel.
+
+# The - indicates the existing use flag must be disabled
+# The (-) indicates that the missing flag is assumed to be disabled
+# if this is simplified to sys-kernel/pentoo-sources[lts?(-)] it would allow users who previously had lts unset to keep non-lts kernel sources installed which breaks the intent
+RDEPEND="
+	sys-kernel/pentoo-sources
+	lts? (
+		sys-kernel/pentoo-sources[lts]
+		!sys-kernel/pentoo-sources[-lts(-)]
+	)
+"