Build for Minecraft 26.1

Adds 26.1 as a Stonecutter version (step 3 of #39). Its jar also
loads on the 26.1.1 and 26.1.2 hotfixes.

Most of 26.1's changes are renames: the GUI's render methods became
extract methods and GuiGraphics became GuiGraphicsExtractor, which
Stonecutter replacements cover along with the moved render state
package and GuiRenderState's add methods. The rest are version
comments:

- The menu panorama is drawn by GuiRenderer from vanilla's cube map;
  the new GuiRendererMixin swaps in Saturn's while a Saturn screen is
  open (empty on older versions).
- The camera works out the FOV and aligns with its entity in
  alignWithEntity, so the zoom and freelook hooks move to CameraMixin.
- Gamma and the menu blur are read while extracting render state.
- The glass blur's post chain takes a Projection and its buffer.
- The dragon's alpha render type is gone; capes use entityCutout.
- Fabric API renamed KeyBindingHelper to KeyMappingHelper.

The docs describe the 26.x build and Java 25.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

stonecutter.gradle.kts

@@ -6,16 +6,23 @@ plugins {
 // "Reset active project" before committing.
 stonecutter active "1.21.11"
 
-// src/ uses the newest Mojang names. These classes were renamed in the versions given, so Stonecutter
-// swaps in the older names when it processes an older version.
+// src/ uses 1.21.11's Mojang names (the active version). These names changed in the versions given,
+// so Stonecutter swaps in each version's name when it processes it.
 stonecutter parameters {
     for ((since, old, new) in listOf(
         Triple("1.21.11", "ResourceLocation", "Identifier"),
         Triple("1.21.9", "PlayerRenderer", "AvatarRenderer"),
         Triple("1.21.9", "PlayerRenderState", "AvatarRenderState"),
+        Triple("26.1", "GuiGraphics", "GuiGraphicsExtractor"),
+        Triple("26.1", "net.minecraft.client.gui.render.state", "net.minecraft.client.renderer.state.gui"),
+        // GuiRenderState's methods
+        Triple("26.1", "submitGuiElement", "addGuiElement"),
+        Triple("26.1", "submitText", "addText"),
+        Triple("26.1", "submitItem", "addItem"),
+        Triple("26.1", "submitPicturesInPictureState", "addPicturesInPictureState"),
     )) {
         replacements.regex(eval(current.version, ">=$since")) {
-            replace("\\b$old\\b", new, "\\b$new\\b", old)
+            replace("\\b${Regex.escape(old)}\\b", new, "\\b${Regex.escape(new)}\\b", old)
         }
     }
 }