feat(ignis): declare Purpur 26.3 support

src/test/java/games/dmg/spigotignis/PurpurDistributionTest.java

@@ -54,6 +54,9 @@ class PurpurDistributionTest {
         assertTrue(build.contains("net.dmulloy2:ProtocolLib:5.4.0"));
         assertFalse(build.contains("26.2") || build.contains("2618"));
         assertFalse(build.contains("org.spigotmc:spigot-api"));
+        String readme = Files.readString(Path.of("README.md"));
+        assertTrue(readme.contains("Purpur `26.3.build.2651-stable`"));
+        assertFalse(readme.contains("26.2") || readme.contains("2618"));
         for (String workflow : new String[] {"ci.yml", "release.yml"}) {
             String content = Files.readString(Path.of(".gitea/workflows", workflow));
             assertTrue(content.contains("java-version: 25"));