Build PRs on ephemeral droplets; publish merged packages from CI

Every pull request now builds the package directories it touches on
ephemeral DigitalOcean droplets, and every merge to master publishes the
resulting artifacts into the channels each package belongs to. The
repository host's timers become the fallback rather than the pipeline.

Build (.github/workflows/build-pr.yml)
  One job per package per architecture, always against edge. The artifact
  is labelled with the package directory's git tree hash. Tooling (bin/,
  helpers/, build/) is checked out from the base branch; the PR supplies
  only pkgbuilds/, so a PR can change what is built, never how. Builds
  run only for trusted authors: collaborators, .github/VOUCHED.td, or a
  PR carrying the build-approved label. A single required check, result,
  aggregates the matrix.

Publish (.github/workflows/publish.yml, bin/publish-artifact)
  One job per merge. It collects the PR artifacts for the merged tree,
  builds anything that has none, then walks each channel/architecture
  slot once: pull that database, repo-add every package that belongs in
  it, upload packages, signatures, then the database. A published
  filename is immutable; identical bytes under an existing name only
  gain a database entry, different bytes are refused. Fast-ring packages
  reach edge, rc and stable in the same run from the same file.

Matrix (bin/build-matrix)
  Package x architecture, with the channels the artifact ships to,
  decided by package_builds_for_mirror so CI and the host agree.
  arch=any packages build once and land in every architecture database.

Builder (build/build.sh, bin/build, build/Dockerfile)
  With no local published tree, plan against and resolve from the public
  channel over HTTPS. PACKAGER is set to Omarchy. rclone is in the image.

Runners (ci/)
  A controller droplet polls GitHub with curl and creates one g5 droplet
  per queued job from cloud-init, deleting them when off or over-age.
  Builders carry QEMU with credential support for aarch64. Operator SSH
  keys come from GitHub. tests/controller.sh and tests/publish-artifact.sh
  cover the decisions against fixtures and real makepkg output.

Tests run on pull requests only; branch protection requires result,
self-tests and build-isolation with up-to-date branches.

build/Dockerfile

@@ -129,6 +129,7 @@ RUN pacman -Syu --noconfirm && \
         wget \
         curl \
         jq \
+        rclone \
         gnupg && \
     pacman -Scc --noconfirm && \
     rm -rf /var/cache/pacman/pkg/*
@@ -146,7 +147,8 @@ RUN useradd -m -G wheel -s /bin/bash builder && \
 # be skipped at signing. Pin the extension so both architectures match.
 RUN sed -i 's/^#MAKEFLAGS=.*/MAKEFLAGS="-j$(nproc)"/' /etc/makepkg.conf && \
     sed -i 's/^COMPRESSZST=.*/COMPRESSZST=(zstd -c -z -q --threads=0 -)/' /etc/makepkg.conf && \
-    sed -i "s|^PKGEXT=.*|PKGEXT='.pkg.tar.zst'|" /etc/makepkg.conf
+    sed -i "s|^PKGEXT=.*|PKGEXT='.pkg.tar.zst'|" /etc/makepkg.conf && \
+    sed -i 's|^#\?PACKAGER=.*|PACKAGER="Omarchy <pkgs@omarchy.org>"|' /etc/makepkg.conf
 
 # Pacman wrapper that auto-resolves package conflicts (e.g. rustup vs rust).
 # makepkg only passes --noconfirm to pacman, which defaults to 'N' on conflict

build/build.sh

@@ -26,6 +26,29 @@ DEFER_RUNTIME_DEPS=${DEFER_RUNTIME_DEPS:-false}
 
 source "$HELPERS_DIR/package-metadata.sh"
 
+# Where the channel's published database is read from for planning. On the
+# repository host it is the published tree itself. Anywhere else (a CI runner,
+# a fresh clone) that tree is absent, so the database is fetched from the
+# public channel and the same URL serves as pacman's dependency repository.
+# Set OMARCHY_PUBLISHED_REPO_URL= (empty) to disable the remote fallback.
+PUBLISHED_REPO_URL=${OMARCHY_PUBLISHED_REPO_URL-https://pkgs.omarchy.org}
+PUBLISHED_DB_DIR="$FINAL_OUTPUT_DIR"
+PUBLISHED_REPO_SERVER=""
+if [[ ! -f "$FINAL_OUTPUT_DIR/omarchy.db.tar.zst" && ! -f "$FINAL_OUTPUT_DIR/omarchy.db" && -n "$PUBLISHED_REPO_URL" ]]; then
+  remote_channel="$PUBLISHED_REPO_URL/$MIRROR/$ARCH"
+  remote_db_dir=$(mktemp -d /tmp/omarchy-published.XXXXXX) || exit 1
+  # Cache-bust: the channel sits behind a CDN that serves a stale database
+  # for a while after a sync.
+  if curl -fsSL "$remote_channel/omarchy.db.tar.zst?$(date +%s)" -o "$remote_db_dir/omarchy.db.tar.zst"; then
+    PUBLISHED_DB_DIR="$remote_db_dir"
+    PUBLISHED_REPO_SERVER="$remote_channel"
+    echo "==> No local published tree; planning against $remote_channel"
+  else
+    rm -rf "$remote_db_dir"
+    echo "==> No local published tree and $remote_channel is unavailable; treating the channel as empty"
+  fi
+fi
+
 if [[ $DEFER_RUNTIME_DEPS != "false" && $DEFER_RUNTIME_DEPS != "true" ]]; then
   echo "DEFER_RUNTIME_DEPS must be true or false" >&2
   exit 1
@@ -118,10 +141,15 @@ if [[ "$DRY_RUN" != true ]]; then
   fi
   touch "$BUILD_PLAN_DIR/repository-initialized" || exit 1
 
-  # Add omarchy repo if it has a database (stable packages)
+  # Add omarchy repo if it has a database (stable packages). The local tree
+  # is trusted as-is; the public channel is verified against the omarchy
+  # keyring the image already carries.
   if [[ -f "$FINAL_OUTPUT_DIR/omarchy.db.tar.zst" ]] || [[ -f "$FINAL_OUTPUT_DIR/omarchy.db" ]]; then
     sudo sed -i "/^\[core\]$/i [omarchy]\nSigLevel = Optional TrustAll\nServer = file://$FINAL_OUTPUT_DIR\n" /etc/pacman.conf
     echo "  -> omarchy (priority 2): $FINAL_OUTPUT_DIR"
+  elif [[ -n "$PUBLISHED_REPO_SERVER" ]]; then
+    sudo sed -i "/^\[core\]$/i [omarchy]\nSigLevel = Required DatabaseOptional\nServer = $PUBLISHED_REPO_SERVER\n" /etc/pacman.conf
+    echo "  -> omarchy (priority 2): $PUBLISHED_REPO_SERVER"
   fi
 
   # Sync pacman database
@@ -159,10 +187,10 @@ LOCAL_VERSION_CACHE_LOADED=false
 LOCAL_VERSION_CACHE_DB=""
 
 load_local_versions() {
-  local db="$FINAL_OUTPUT_DIR/omarchy.db.tar.zst"
+  local db="$PUBLISHED_DB_DIR/omarchy.db.tar.zst"
 
   if [[ ! -f "$db" ]]; then
-    db="$FINAL_OUTPUT_DIR/omarchy.db"
+    db="$PUBLISHED_DB_DIR/omarchy.db"
   fi
 
   [[ -f "$db" ]] || return 0