build: add neovim to devcontainer

.devcontainer/Dockerfile

@@ -9,6 +9,12 @@ RUN apt-get update && apt-get install -y \
     ca-certificates \
     && rm -rf /var/lib/apt/lists/*
 
+# Install latest neovim using pre-built binary
+RUN curl -LO https://github.com/neovim/neovim/releases/latest/download/nvim-linux-x86_64.tar.gz \
+    && tar -C /opt -xzf nvim-linux-x86_64.tar.gz \
+    && ln -s /opt/nvim-linux-x86_64/bin/nvim /usr/local/bin/nvim \
+    && rm nvim-linux-x86_64.tar.gz
+
 # Install lazygit
 RUN LAZYGIT_VERSION=$(curl -s "https://api.github.com/repos/jesseduffield/lazygit/releases/latest" | grep -Po '"tag_name": "v\K[^"]*') \
     && curl -Lo lazygit.tar.gz "https://github.com/jesseduffield/lazygit/releases/latest/download/lazygit_${LAZYGIT_VERSION}_Linux_x86_64.tar.gz" \