Starting with 26.1 Mojang ships Minecraft unobfuscated, and Yarn /
Intermediary are no longer published past 1.21.11. Loom does not need
a mappings dependency in that mode: the Mojang-named source compiles
directly. Remove the mappings line, drop the yarn_mappings property,
revert the client entrypoint to Mojang names (Minecraft, Component,
ChatFormatting, gui.getChat(), getUser().getName()), and rewrite the
README note so it stops claiming Mojang mappings via Loom.
Loom rejected officialMojangMappings() with a non-obfuscated
environment error, and Mojang client_mappings are not published for
26.2 yet. Pin Yarn at 26.2+build.3 via the new yarn_mappings property
and rewrite the client entrypoint with Yarn names: MinecraftClient,
Text, Formatting, inGameHud.getChatHud(), getSession().getUsername().
Gradle 9 rejects property interpolation inside plugins {} — the version
must be a literal String. Drop the now-unused loom_version key from
gradle.properties so it does not desync from the build script.
