refactor: optimize Dockerfile for Flutter Android environment

flutter-android/Dockerfile

@@ -1,12 +1,22 @@
-FROM ubuntu:22.04
+FROM ubuntu:22.04-slim
 
 ENV DEBIAN_FRONTEND=noninteractive
+
+# ===== ВЕРСИИ (фиксируем для стабильности CI) =====
+ENV FLUTTER_VERSION=3.19.6
+ENV ANDROID_API=34
+ENV ANDROID_BUILD_TOOLS=34.0.0
+ENV ANDROID_CMDLINE_TOOLS=11076708
+
+# ===== ПУТИ =====
 ENV ANDROID_HOME=/opt/android-sdk
 ENV ANDROID_SDK_ROOT=/opt/android-sdk
 ENV FLUTTER_HOME=/opt/flutter
+ENV GRADLE_USER_HOME=/opt/gradle
+
 ENV PATH=$PATH:$ANDROID_HOME/cmdline-tools/latest/bin:$ANDROID_HOME/platform-tools:$FLUTTER_HOME/bin
 
-# Установка зависимостей
+# ===== БАЗОВЫЕ ПАКЕТЫ =====
 RUN apt-get update && apt-get install -y \
     curl \
     git \
@@ -17,32 +27,43 @@ RUN apt-get update && apt-get install -y \
     openjdk-17-jdk \
     wget \
     ca-certificates \
+    bash \
+    libc6 \
+    libstdc++6 \
     && rm -rf /var/lib/apt/lists/*
 
-# Установка Android SDK command line tools
-RUN mkdir -p $ANDROID_HOME/cmdline-tools
-WORKDIR $ANDROID_HOME/cmdline-tools
-
-RUN wget https://dl.google.com/android/repository/commandlinetools-linux-11076708_latest.zip -O sdk-tools.zip \
+# ===== ANDROID SDK =====
+RUN mkdir -p ${ANDROID_HOME}/cmdline-tools \
+    && cd ${ANDROID_HOME}/cmdline-tools \
+    && wget https://dl.google.com/android/repository/commandlinetools-linux-${ANDROID_CMDLINE_TOOLS}_latest.zip -O sdk-tools.zip \
     && unzip sdk-tools.zip \
     && rm sdk-tools.zip \
     && mv cmdline-tools latest
 
-# Принимаем лицензии и устанавливаем платформы
+# Принимаем лицензии
 RUN yes | sdkmanager --licenses
 
+# Устанавливаем только нужное
 RUN sdkmanager \
     "platform-tools" \
-    "platforms;android-34" \
-    "build-tools;34.0.0"
+    "platforms;android-${ANDROID_API}" \
+    "build-tools;${ANDROID_BUILD_TOOLS}"
 
-# Установка Flutter
-WORKDIR /opt
-RUN git clone https://github.com/flutter/flutter.git -b stable
+# ===== FLUTTER =====
+RUN git clone https://github.com/flutter/flutter.git \
+    --branch ${FLUTTER_VERSION} \
+    --depth 1 \
+    ${FLUTTER_HOME}
 
-# Предварительная инициализация
-RUN flutter doctor
-RUN flutter precache
+# Precache только Android (без web, linux, macOS)
+RUN flutter precache --android
+
+# ===== GRADLE (предварительный warmup) =====
+RUN mkdir -p ${GRADLE_USER_HOME}
+
+# ===== ОЧИСТКА МУСОРА =====
+RUN rm -rf /root/.cache \
+    && rm -rf ${ANDROID_HOME}/.android \
+    && rm -rf /tmp/*
 
-# Рабочая директория
 WORKDIR /app