docker: fix more issues with dynamic linking

Dockerfile

@@ -9,37 +9,49 @@ ARG YT_DLP_VERSION="2026.03.03"
 # Deno builder stage
 FROM denoland/deno:bin-2.6.6@sha256:9f18d20207f2699595ea26d14e0b7e123cd0cd01100a577bc11f8ca5906c2d81 AS deno-builder
 
-################################################################################
-# FFmpeg builder stage
-FROM debian:13-slim@sha256:1d3c811171a08a5adaa4a163fbafd96b61b87aa871bbc7aa15431ac275d3d430 AS ffmpeg-builder
-RUN apt-get update && \
-  apt-get install -y --no-install-recommends ffmpeg
-RUN mkdir -p /rootfs/bin && \
-  cp /usr/bin/ffmpeg /usr/bin/ffprobe /rootfs/bin/ && \
-  ldd /usr/bin/ffmpeg | awk '{print $3}' | grep "^/" | xargs -I '{}' cp --parents '{}' /rootfs && \
-  ldd /usr/bin/ffmpeg | awk 'NF==2 {print $1}' | grep "^/" | xargs -I '{}' cp --parents '{}' /rootfs
-
 ################################################################################
 # YT-DLP builder stage
 FROM alpine:3.23@sha256:25109184c71bdad752c8312a8623239686a9a2071e8825f20acb8f2198c3f659 AS yt-dlp-builder
 ARG YT_DLP_VERSION
+ARG TARGETARCH
 
 RUN mkdir -p /rootfs/target /rootfs/tmp /rootfs/bin
 
-ADD "https://github.com/yt-dlp/yt-dlp/releases/download/${YT_DLP_VERSION}/yt-dlp_linux" /yt-dlp_linux
 ADD "https://github.com/yt-dlp/yt-dlp/releases/download/${YT_DLP_VERSION}/SHA2-256SUMS" /SHA2-256SUMS
 ADD "https://github.com/yt-dlp/yt-dlp/releases/download/${YT_DLP_VERSION}/SHA2-256SUMS.sig" /SHA2-256SUMS.sig
 ADD "https://keyserver.ubuntu.com/pks/lookup?op=get&search=0xAC0CBBE6848D6A873464AF4E57CF65933B5A7581" "/yt-dlp_pubkey.asc"
 
 RUN apk add --no-cache gnupg && \
   gpg --import /yt-dlp_pubkey.asc && \
-  gpg --verify /SHA2-256SUMS.sig /SHA2-256SUMS && \
-  grep " yt-dlp_linux$" /SHA2-256SUMS | sha256sum -c -
+  gpg --verify /SHA2-256SUMS.sig /SHA2-256SUMS
 
-RUN mv /yt-dlp_linux /rootfs/bin/yt-dlp && \
+RUN case "$TARGETARCH" in \
+    amd64) YT_DLP_FILE="yt-dlp_linux" ;; \
+    arm64) YT_DLP_FILE="yt-dlp_linux_aarch64" ;; \
+    *) echo "Unsupported architecture: $TARGETARCH" && exit 1 ;; \
+  esac && \
+  wget -qO "/${YT_DLP_FILE}" "https://github.com/yt-dlp/yt-dlp/releases/download/${YT_DLP_VERSION}/${YT_DLP_FILE}" && \
+  grep " ${YT_DLP_FILE}$" /SHA2-256SUMS | sha256sum -c - && \
+  mv "/${YT_DLP_FILE}" /rootfs/bin/yt-dlp && \
   chmod 755 /rootfs/bin/yt-dlp && \
   chmod 1777 /rootfs/tmp
 
+################################################################################
+# FFmpeg builder stage
+FROM debian:13-slim@sha256:1d3c811171a08a5adaa4a163fbafd96b61b87aa871bbc7aa15431ac275d3d430 AS ffmpeg-builder
+RUN apt-get update && \
+  apt-get install -y --no-install-recommends ffmpeg
+COPY --from=yt-dlp-builder /rootfs/bin/yt-dlp /yt-dlp
+RUN mkdir -p /rootfs/bin && \
+  cp /usr/bin/ffmpeg /usr/bin/ffprobe /rootfs/bin/ && \
+  { ldd /usr/bin/ffmpeg; ldd /yt-dlp; } 2>/dev/null | \
+  grep -o '/[^ ]*' | sort -u | \
+  xargs -I '{}' cp --parents '{}' /rootfs && \
+  LIBDIR=$(dirname "$(find /rootfs -name 'libc.so.6' | head -1)") && \
+  for stub in libutil.so.1 libdl.so.2 libpthread.so.0 librt.so.1; do \
+    [ -f "${LIBDIR}/${stub}" ] || ln -sf libc.so.6 "${LIBDIR}/${stub}"; \
+  done
+
 ################################################################################
 # App builder stage
 FROM golang:1.25.8-trixie@sha256:bc16125656839ffe56154c675f7a9662bec2ef7d4060177239914e7c6d2fd8a8 AS app-builder
@@ -76,4 +88,4 @@ LABEL org.opencontainers.image.title="yt-dlp bot" \
   org.opencontainers.image.authors="William Peebles <me@williamtpeebles.com>" \
   org.opencontainers.image.vendor="William Peebles" \
   org.opencontainers.image.licenses="MIT" \
-  org.opencontainers.image.source="https://git.dubyatp.xyz/williamp/yt-dlp-bot"
+  org.opencontainers.image.source="https://git.dubyatp.xyz/williamp/yt-dlp-bot"