26.x ships unobfuscated, so there is no Yarn: everything is compiled
directly against Mojang names. The GUI also moved from immediate-mode
rendering to render-state extraction, so screens no longer override
render(DrawContext) but extractRenderState(GuiGraphicsExtractor), and
widgets render themselves once added.

Build:
- Loom 1.17 plain plugin (no -remap), no mappings dependency, Gradle 9.5.1
- Java 25, fabric-loader 0.19.3, fabric-api 0.154.2+26.1.2

API migration highlights:
- Session -> User (getUser/getName/getProfileId)
- Text -> Component, Formatting -> ChatFormatting, .formatted -> .withStyle
- ButtonWidget -> Button (.dimensions -> .bounds), TextFieldWidget -> EditBox
- MultiplayerScreen -> JoinMultiplayerScreen, this.client -> this.minecraft
- ClientCommandManager -> ClientCommands
- KeyBindingHelper -> KeyMappingHelper (fabric-key-mapping-api-v1)
- TelemetryManager -> ClientTelemetryManager (TelemetryEventSender.DISABLED)
- KeyInput -> KeyEvent (input.key())

Scoped out of the 26.x port (cosmetic, restorable):
- DownloaderMixin: redirected an intermediary-only method with no Mojmap
  equivalent; its "isolate pack cache" toggle is hidden accordingly
- SkinCache head textures: the NativeImage upload pipeline changed; rows
  fall back to placeholder avatars
- In-world HUD alt indicator and ModMenu integration

…r>.jar)