Use dynamic architecture detection for linux-headers package

Replace hardcoded linux-headers-amd64 with linux-headers-$(dpkg --print-architecture)
to support both amd64 and arm64 builds.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: koki-develop

repo/Dockerfile

@@ -3,7 +3,7 @@ ENV DEBIAN_FRONTEND=noninteractive
 RUN apt-get update && apt-get install -y unzip autoconf build-essential libssl-dev \
         pkg-config zlib1g-dev libargon2-dev libsodium-dev libcurl4-openssl-dev \
         sqlite3 libsqlite3-dev libonig-dev libxml2 libxml2-dev bc curl git \
-        linux-headers-amd64 perl xz-utils python3 python3-pip gnupg jq zlib1g-dev \
+        linux-headers-$(dpkg --print-architecture) perl xz-utils python3 python3-pip gnupg jq zlib1g-dev \
         cmake cmake-doc extra-cmake-modules build-essential gcc binutils bash coreutils \
         util-linux pciutils usbutils coreutils binutils findutils grep libncurses-dev \
         python3-pip libgmp-dev libmpfr-dev libffi-dev gfortran \