Backport 1.21.1 optimizations to 1.20.1

[rsdadada]

• 已回移植

• common/src/main/java/com/xtracr/realcamera/config/BindTarget.java

  • DisableConfig 改为带 UV 缓存的 class + @JsonAdapter
  • JSON 结构保持兼容
  • 新增 disable(...)：缓存判定并用可变 FloatOpenHashSet 适配 1.20.1

• common/src/main/java/com/xtracr/realcamera/RealCameraCore.java

  • 禁用判定统一用 config.disable(...)
  • 保留 1.20.1 view-space 渲染与 vertex.z() 深度裁剪（未引入 modelView 路径）

• common/src/main/java/com/xtracr/realcamera/mixin/MixinLevelRenderer.java

  • 保持 1.20.1 renderLevel 注入签名与调用路径
  • 不从 PoseStack 提取 modelView

• common/src/main/java/com/xtracr/realcamera/gui/ModelAnalyser.java

  • 修复 deltaZ 符号导致的选面排序不稳定
  • 禁用判定统一用 config.disable(...)

• common/src/main/java/com/xtracr/realcamera/config/ModConfig.java

  • activeConfigIndex 增加下界保护（<=0 返回全部，并 clamp 到 >=0）

• 未同步

• 平台/构建与模块迁移（Java 21、NeoForge、Gradle/Loom/Wrapper、CI 与模板）未引入：

  • build.gradle
  • settings.gradle
  • gradle.properties
  • gradle/wrapper/
  • gradlew
  • gradlew.bat
  • .github/workflows/
  • .github/ISSUE_TEMPLATE/
  • forge/
  • neoforge/
  • fabric/build.gradle
  • fabric/src/main/resources/fabric.mod.json

• 新渲染管线与顶点 API（MeshData、ByteBufferBuilder、VertexConsumer.addVertex、FastColor）未回移：（1.20.1 没这些类与接口语义）

  • common/src/main/java/com/xtracr/realcamera/util/BuiltIterableBuffer.java
  • common/src/main/java/com/xtracr/realcamera/util/IterableVertexBuffer.java
  • common/src/main/java/com/xtracr/realcamera/util/MultiVertexCatcher.java
  • common/src/main/java/com/xtracr/realcamera/util/VertexData.java
  • common/src/main/java/com/xtracr/realcamera/gui/GUIHelper.java
  • common/src/main/java/com/xtracr/realcamera/gui/ModelViewScreen.java
  • common/src/main/java/com/xtracr/realcamera/gui/ModelAnalyser.java
  • common/src/main/java/com/xtracr/realcamera/gui/TexturedButton.java
  • common/src/main/java/com/xtracr/realcamera/gui/NumberField.java
  • common/src/main/java/com/xtracr/realcamera/gui/CyclingTexturedButton.java

• 渲染循环与 mixin 签名变更（DeltaTracker、modelView/projection、TickRateManager、交互距离、roll 注入）及配置更新未回移：（1.20.1 没有新接口）

  • common/src/main/java/com/xtracr/realcamera/mixin/MixinGameRenderer.java
  • common/src/main/java/com/xtracr/realcamera/mixin/MixinLevelRenderer.java
  • common/src/main/java/com/xtracr/realcamera/mixin/MixinGui.java
  • common/src/main/java/com/xtracr/realcamera/RealCameraCore.java
  • common/src/main/resources/realcamera-common.mixins.json
  • common/src/main/resources/realcamera.accesswidener
  • fabric/src/main/resources/realcamera.mixins.json
  • fabric/src/main/java/com/xtracr/realcamera/EventHandler.java
  • fabric/src/main/java/com/xtracr/realcamera/mixin/GameRendererEvents.java

• Java 21 API/语言特性依赖未回移（Math.clamp、SequencedMap、List.getFirst/removeFirst、record pattern）：

  • common/src/main/java/com/xtracr/realcamera/config/ModConfig.java
  • common/src/main/java/com/xtracr/realcamera/util/MultiVertexCatcher.java
  • common/src/main/java/com/xtracr/realcamera/gui/ModelAnalyser.java
  • common/src/main/java/com/xtracr/realcamera/util/VertexData.java

• 经典视角/渲染器签名调整未回移（Z 方向反号、move float、PlayerRendererAccessor 额外缩放参数）：

  • common/src/main/java/com/xtracr/realcamera/mixin/MixinCamera.java
  • common/src/main/java/com/xtracr/realcamera/compat/LegacyBindingMode.java
  • common/src/main/java/com/xtracr/realcamera/mixin/accessor/PlayerRendererAccessor.java
  • common/src/main/java/com/xtracr/realcamera/mixin/MixinPlayerRenderer.java

• 兼容层与渲染重定向差异未回移（TACZ 兼容删除、ResourceLocation.parse、YSMCompat 不再处理 normal、钓鱼线手部渲染签名变化）：

  • common/src/main/java/com/xtracr/realcamera/compat/CompatibilityHelper.java
  • common/src/main/java/com/xtracr/realcamera/compat/DisableHelper.java
  • common/src/main/java/com/xtracr/realcamera/compat/YSMCompat.java
  • common/src/main/java/com/xtracr/realcamera/mixin/MixinFishingHookRenderer.java