Add file-io 0.2.0 to git-annex build environment

[yarikoptic-gitmate]

Summary

This change adds the file-io Haskell package (version 0.2.0) to the git-annex build environment Docker image to enable the OsPath build flag in git-annex.

Key Changes

• Added installation of file-io 0.2.0 from Hackage into the global GHC package database
• Included SHA256 verification of the downloaded tarball for security
• Configured and built file-io using Cabal's Setup.hs mechanism with global installation

Implementation Details

The file-io package is required because:

• git-annex's OsPath build flag (enabled by default) depends on file-io >= 0.2.0 since version 10.20260213
• Debian's libghc-file-io-dev package only provides version 0.1.5, which is insufficient
• OsPath enables important fixes for file handling on systems like BeeGFS

The installation:

• Downloads the package from Hackage with checksum verification
• Builds and installs it globally so it's available to subsequent builds
• Uses only GHC boot packages as dependencies, avoiding additional package requirements
• Includes a note that this workaround can be removed once Debian provides libghc-file-io-dev >= 0.2.0

https://claude.ai/code/session_013n9Q2igij49kxdtiakUzYv

[yarikoptic]

The build check (Build Linux buildenv image, run 36139747634) was cancelled at the 6h job timeout. That is not caused by this PR's change: the job never reached the new file-io step. It hung in the first, pre-existing RUN layer, at nd_freeze 20260425 → INFO: Refreshing apt cache. That is apt update against snapshot.debian.org, and the log has no output after 13:15:50 until the cancel at 19:15:18. Previous runs of this workflow took about 2.5h, most of it downloading from snapshot.debian.org.

No fix exists for that yet. Hardening it (e.g. Acquire::http::Timeout next to the existing Dl-Limit/Retries settings, or timeout-minutes on the job) would be a separate change, so I have not widened this PR with it. I'm re-running the job once.

The new step itself was verified locally, layered on the current datalad/buildenv-git-annex:latest:

• ghc-pkg field file-io version gives version: 0.2.0.
• A full make debianstandalone-dsc plus dpkg-buildpackage -b of upstream 10.20260901+git60 reports build flags: ... Servant OsPath.
• git annex test on that build: all 26 test groups pass.

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[yarikoptic]

The re-run hung at the same point: nd_freeze 20260425 → INFO: Refreshing apt cache, then no output from 19:17:20 until the 6h cancel at 01:16:35. Two identical 6h hangs means this is not a flake. So I've pushed 7942b06, which replaces nd_freeze with apt sources pinned to snapshot.debian.org directly.

Most likely cause. After its first apt-get update, nd_freeze's write_snapshot_sources scrapes snapshot.debian.org with get_www_content. That is a raw-socket HTTP/1.1 GET with no Connection: close and no timeout, which reads until EOF. It logs nothing unless --debug is given, so a stalled connection there looks exactly like these logs.

Change:

• ARG DEBIAN_SNAPSHOT=20260924T000000Z feeds a deb822 debian-snapshot.sources for forky / forky-updates / forky-security, with Types: deb deb-src (needed by build-dep).
• Acquire::Check-Valid-Until "false", since snapshot Release files are past their Valid-Until.
• Acquire::http::Timeout "120", so a stalled transfer fails into the existing Retries 10 instead of hanging.
• Dropped the neurodebian-freeze install, the debian.sources → .disabled dance and the deb-src sed, which only existed for nd_freeze.
• build-linux-buildenv.yaml derived the tag date by grepping for nd_freeze. It now reads DEBIAN_SNAPSHOT, so tags stay forky-YYYYMMDD-<commit> (here forky-20260924-…).

Note: the snapshot date moves from 2026-04-25 to 2026-09-24, so the GHC / libghc-* set may change. Once this image builds, OsPath needs re-checking in a standalone build. The file-io step becomes redundant, but harmless, if Debian has meanwhile shipped file-io ≥ 0.2.0.

Tested locally only up to apt: the ARG expands, apt accepts the sources, and apt-get update --print-uris lists the expected InRelease, Packages.xz and Sources.xz URIs. snapshot.debian.org itself is not reachable from where I tested.

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Generated by Claude Code