refactor: use alpine for web app

[sghng]

No description provided.

[Copilot]

Pull request overview

This PR refactors the Dockerfile to use Alpine Linux-based images instead of Debian/slim variants, aiming to reduce image size and simplify the build process. The changes migrate all base images (rust, typst, pandoc, and bun) to Alpine variants and update package management from apt to apk.

Key Changes:

• Migrated from Debian-based images (rust:slim, rust:slim-bookworm) to Alpine-based images (rust:alpine, alpine:edge, oven/bun:alpine)
• Simplified build stages by using pre-built Alpine packages for typst instead of building from source
• Replaced custom pandoc download logic with the official pandoc/minimal image
• Updated all package installations from apt to apk with corresponding Alpine package names

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[Copilot]

The Alpine package name should be pkgconf instead of pkgconfig. In Alpine Linux, the pkg-config implementation is provided by the pkgconf package. Using pkgconfig may cause the build to fail.

Suggested change

	RUN apk add pkgconfig openssl-dev uv gcompat
	RUN apk add pkgconf openssl-dev uv gcompat

[Copilot]

Installing uv via apk requires adding the community or testing repository, as it's not available in the main Alpine repository. Consider either adding the repository explicitly (e.g., RUN apk add --repository=http://dl-cdn.alpinelinux.org/alpine/edge/testing uv) or reverting to the curl installation method from the original version to ensure the build succeeds reliably.

Suggested change

	RUN apk add pkgconfig openssl-dev uv gcompat
	RUN apk add pkgconfig openssl-dev gcompat && \
	apk add --repository=http://dl-cdn.alpinelinux.org/alpine/edge/testing uv

[Copilot]

Using alpine:edge provides the latest rolling release packages but can introduce instability and breaking changes. Consider using a stable Alpine version (e.g., alpine:3.20) with an explicit typst version for better reproducibility and reliability in production environments.

Suggested change

	FROM alpine:edge AS typst
	RUN apk add typst
	FROM alpine:3.20 AS typst
	RUN apk add --no-cache ca-certificates wget tar
	# Install specific typst version (e.g., v0.10.0)
	ENV TYPST_VERSION=0.10.0
	RUN wget -O typst.tar.xz https://github.com/typst/typst/releases/download/v${TYPST_VERSION}/typst-x86_64-unknown-linux-musl.tar.xz \
	&& tar -xf typst.tar.xz \
	&& mv typst-x86_64-unknown-linux-musl/typst /usr/bin/typst \
	&& rm -rf typst-x86_64-unknown-linux-musl typst.tar.xz

[Copilot]

The gcompat package provides GNU libc compatibility for musl-based Alpine, which is needed for Python packages like saxonche (listed in pyproject.toml) that have glibc dependencies. However, gcompat may not fully support all glibc features. Consider testing thoroughly to ensure all Python dependencies (especially saxonche, pdfservices-sdk, and pdf2docx) work correctly with musl/gcompat, or document any known limitations.

Suggested change

	FROM rust:alpine AS typ2docx
	FROM rust:alpine AS typ2docx
	# NOTE: gcompat provides partial GNU libc compatibility for musl-based Alpine.
	# Some Python packages (e.g., saxonche, pdfservices-sdk, pdf2docx) may require full glibc support.
	# gcompat may not fully support all glibc features; test these packages thoroughly and document any known limitations.

[Copilot]

Missing the --no-cache flag for apk add commands. Adding this flag (e.g., RUN apk add --no-cache ...) prevents caching the package index and reduces the final image size, which is a best practice for Alpine-based Docker images.