Replace vendored docker-compose with podman-compose

podman-compose and docker-compose aren't discovered the same way by
`podman compose` - verified live (a fake-binary test reading podman's own
provider-search error output) that docker-compose is searched for by
exact path across a fixed list of CLI-plugin directories, while
podman-compose is instead looked up as a plain command on $PATH. This
package installs to /usr/local/bin/podman-compose accordingly, not under
any cli-plugins/ directory.

Unlike docker-compose (a single static Go binary), podman-compose is a
Python script with two runtime dependencies neither of which ship with
Unraid's own Python3 - PyYAML and python-dotenv, vendored here as plain
pure-Python source (no C extension build; PyYAML's own fallback handles
its optional C accelerator being absent).

Verified end-to-end on a real host: with the previous docker-compose
binary temporarily moved aside to confirm podman-compose was actually the
one invoked, `podman compose up/ps/down` ran a real compose project
correctly, including a live HTTP check against the started service.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

packages/podman-compose/README.md

@@ -0,0 +1,34 @@
+# packages/podman-compose/
+
+Pinned versions: see `PODMAN_COMPOSE_VERSION`/`PYYAML_VERSION`/
+`PYTHON_DOTENV_VERSION` in [versions.env](../../versions.env).
+
+`podman compose` (backing `webui/plugins/podman/ajax/compose.php`, the
+WebUI's Compose panel) has no compose implementation of its own — it
+needs an external "compose provider" command. This project previously
+vendored `docker/compose` (the Go CLI-plugin binary) for that role;
+this package replaces it with `podman-compose` instead.
+
+The two aren't discovered the same way — verified live against a real
+podman install (placing a fake executable and reading podman's own
+provider-search error output): `docker-compose` is searched for by exact
+path across a fixed list of CLI-plugin directories, while `podman-compose`
+is looked up as a plain command on `$PATH`. That's why this package
+installs to `/usr/local/bin/podman-compose` rather than under any
+`cli-plugins/` directory.
+
+Unlike `docker-compose`, `podman-compose` is a single Python script, not a
+compiled binary. Unraid ships Python3 itself but neither of its two
+runtime dependencies, so this package also vendors:
+
+- `PyYAML` — only the pure-Python `yaml/` package, not the `_yaml` C
+  extension (which would need libyaml plus a compiler). `yaml/__init__.py`
+  falls back gracefully when the C accelerator isn't importable, so the
+  pure-Python source is sufficient for what podman-compose needs from it.
+- `python-dotenv` — pure Python throughout, no C extensions at all.
+
+Verified end-to-end on a real Unraid host: the vendored bundle correctly
+runs `podman compose up`/`ps`/`down` against a real compose project
+(with the pre-existing `docker-compose` binary temporarily moved aside
+to confirm `podman-compose` was the one actually being invoked, not a
+leftover), including a live HTTP check against the started service.

packages/podman-compose/podman-compose.SlackBuild

@@ -0,0 +1,83 @@
+#!/bin/bash
+# =============================================================================
+# packages/podman-compose/podman-compose.SlackBuild
+#
+# Packages podman-compose (github.com/containers/podman-compose) — the
+# external "compose provider" `podman compose` shells out to (see
+# versions.env's PODMAN_COMPOSE_* block for the full story, including why
+# this replaces the project's earlier vendored docker-compose). Verified
+# live against a real podman install that podman-compose is looked up as a
+# plain $PATH command, unlike docker-compose's fixed CLI-plugin-directory
+# search — so this installs a wrapper at /usr/local/bin/podman-compose.
+#
+# podman-compose itself is a single Python script (not a compiled binary),
+# with two runtime dependencies — PyYAML and python-dotenv — vendored here
+# as plain pure-Python source (no C extension build) since Unraid ships
+# Python3 but neither of those modules.
+# =============================================================================
+
+set -eu
+
+REPO_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
+# shellcheck source=/dev/null
+. "$REPO_ROOT/scripts/lib/slackbuild-common.sh"
+# shellcheck source=/dev/null
+. "$REPO_ROOT/versions.env"
+
+VERSION="$PODMAN_COMPOSE_VERSION"
+ARCH="$PKG_ARCH"
+BUILD="$PKG_BUILD"
+TAG="$PKG_TAG"
+
+sb_init "podman-compose"
+
+script=$(sb_fetch_and_verify "$PODMAN_COMPOSE_SRC_URL" "$PODMAN_COMPOSE_SRC_SHA256" "podman_compose-$VERSION.py")
+pyyaml_tarball=$(sb_fetch_and_verify "$PYYAML_SRC_URL" "$PYYAML_SRC_SHA256" "pyyaml-$PYYAML_VERSION.tar.gz")
+dotenv_tarball=$(sb_fetch_and_verify "$PYTHON_DOTENV_SRC_URL" "$PYTHON_DOTENV_SRC_SHA256" "python-dotenv-$PYTHON_DOTENV_VERSION.tar.gz")
+
+libdir="$PKG/usr/local/lib/podman-compose"
+mkdir -p "$libdir"
+install -m 0644 "$script" "$libdir/podman_compose.py"
+
+# Only the pure-Python "yaml" package, not the "_yaml" C extension (which
+# would need libyaml plus a compiler toolchain this build doesn't otherwise
+# require) — see the header comment on why the pure-Python fallback is
+# sufficient for what podman-compose actually needs from it.
+tar -xzf "$pyyaml_tarball" -C "$TMP" "pyyaml-$PYYAML_VERSION/lib/yaml"
+cp -r "$TMP/pyyaml-$PYYAML_VERSION/lib/yaml" "$libdir/yaml"
+
+tar -xzf "$dotenv_tarball" -C "$TMP" "python_dotenv-$PYTHON_DOTENV_VERSION/src/dotenv"
+cp -r "$TMP/python_dotenv-$PYTHON_DOTENV_VERSION/src/dotenv" "$libdir/dotenv"
+
+# A thin wrapper, not a symlink or bare shebang: podman_compose.py's own
+# shebang (whatever upstream wrote, a plain "#!/usr/bin/env python3") has
+# no idea the vendored yaml/dotenv sit right next to it, so PYTHONPATH has
+# to be set by whatever actually invokes the script.
+install -d "$PKG/usr/local/bin"
+cat > "$PKG/usr/local/bin/podman-compose" <<'WRAPPER'
+#!/bin/sh
+exec env PYTHONPATH="/usr/local/lib/podman-compose${PYTHONPATH:+:$PYTHONPATH}" \
+  /usr/bin/python3 /usr/local/lib/podman-compose/podman_compose.py "$@"
+WRAPPER
+chmod 0755 "$PKG/usr/local/bin/podman-compose"
+
+docdir="$PKG/usr/doc/podman-compose-$VERSION"
+mkdir -p "$docdir"
+{
+  echo "podman-compose $VERSION"
+  echo "https://github.com/containers/podman-compose"
+  echo
+  echo "Vendored alongside its two runtime dependencies (bundled as plain"
+  echo "pure-Python source, no C extensions built):"
+  echo "  PyYAML $PYYAML_VERSION - https://pypi.org/project/PyYAML/"
+  echo "  python-dotenv $PYTHON_DOTENV_VERSION - https://pypi.org/project/python-dotenv/"
+  echo
+  echo "See versions.env for pinned source URLs and SHA256 checksums."
+} > "$docdir/README"
+{
+  echo "Built by unraid-podman from upstream source."
+  echo "Package: podman-compose $VERSION"
+  echo "Built:   $(date -u +%Y-%m-%dT%H:%M:%SZ)"
+} > "$docdir/unraid-podman.build-info"
+
+sb_make_package "$VERSION" "$ARCH" "$BUILD" "$TAG"

packages/podman-compose/slack-desc

@@ -0,0 +1,19 @@
+# HOW TO EDIT THIS FILE:
+# The "handy ruler" below makes it easier to edit a package description.
+# Line up the first '|' above the ':' following the base package name, and
+# the '|' on the right side marks the last column you can put a character in.
+# You must make exactly 11 lines for the formatting to be correct. It's also
+# customary to leave one space after the ':' except on otherwise blank lines.
+
+        |-----handy-ruler------------------------------------------------|
+podman-compose: podman-compose (external Compose provider for podman compose)
+podman-compose:
+podman-compose: A Python script that implements Docker Compose file support
+podman-compose: on top of podman, installed to /usr/local/bin so
+podman-compose: `podman compose` finds it as its external provider.
+podman-compose: Required by the WebUI's Compose panel. Bundled with its
+podman-compose: two runtime dependencies (PyYAML, python-dotenv) as plain
+podman-compose: pure-Python source.
+podman-compose:
+podman-compose: Homepage: https://github.com/containers/podman-compose
+podman-compose: