dev-libs/stb: Bump to 20260415, EAPI 9, fix for prefix

Closes: https://bugs.gentoo.org/674394
Closes: https://bugs.gentoo.org/931597
Signed-off-by: James Le Cuirot <chewi@gentoo.org>

dev-libs/stb/Manifest

@@ -1 +1,2 @@
 DIST stb-20240201.tar.gz 1510288 BLAKE2B f11e802c6e9efe60bf08bb6071b6e8a12fc7a0713f450379534c2a4fc96c2023a190f4fed598fa7fa9b577e19f14bffbfa2f54dff1ebf72d933dc0113aa820c5 SHA512 2403ddb14b7c1a49f12bb0b43e52c612d58e4382ed03f59b4255560900eb7f08651b6688ec8b468b89e999611a67de5bd1102aa03d3847e3dd2d464175a11905
+DIST stb-20260415.tar.gz 1516082 BLAKE2B e03cd198f860b89fcb21142f2f57aea98541f86e10f74b8d5c1693578b169a6982d8b9758df24d870d935d6e496793a256ad94e1efafaba0a1ec4c738bf0a2ed SHA512 0cffbd63fbe739af23dd2e36307c2f846b9a91b0bd89007f471abe570aca52edb96d256a361c5677c3227009587aebd680abf56e9ecb50f89327414d4f343542

dev-libs/stb/stb-20260415.ebuild

@@ -0,0 +1,41 @@
+# Copyright 1999-2026 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=9
+
+# There are no official releases
+CHECKSUM="31c1ad37456438565541f4919958214b6e762fb4"
+
+DESCRIPTION="Single-file C/C++ libraries for various purposes"
+HOMEPAGE="https://github.com/nothings/stb"
+SRC_URI="https://github.com/nothings/stb/archive/${CHECKSUM}.tar.gz -> ${P}.tar.gz"
+
+S="${WORKDIR}/${PN}-${CHECKSUM}"
+
+LICENSE="|| ( MIT Unlicense )"
+SLOT="0"
+KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~hppa ~loong ~ppc ~ppc64 ~riscv ~sparc ~x86"
+
+src_prepare() {
+	default
+
+	# Move the header files in a folder so they don't pollute the include dir
+	mkdir stb || die
+	mv *.h stb/ || die
+	mv deprecated stb/ || die
+}
+
+src_install() {
+	doheader -r stb
+
+	insinto /usr/share/pkgconfig
+	newins - stb.pc <<-EOF
+	prefix="${EPREFIX}/usr"
+	includedir=\${prefix}/include/stb
+
+	Name: stb
+	Description: ${DESCRIPTION}
+	Version: ${PV}
+	Cflags: -I\${includedir}
+	EOF
+}