fix: service file crash on fresh installs, CI workflow portability

- Remove MemoryDenyWriteExecute=yes from archipelago.service — ring
  (rustls) and secp256k1 (bitcoin/nostr) crypto libraries need
  executable memory mappings that this restriction blocks
- Add + prefix to ExecStartPre so mkdir/chown run as root
- Use $HOME/archy instead of /home/archipelago/archy in CI workflows
  so builds work on both .228 and VPS CI runners

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitea/workflows/build-iso-dev.yml

@@ -13,13 +13,14 @@ jobs:
       - name: Checkout
         run: |
           # Direct fetch + sync (actions/checkout token is broken on this Gitea)
-          cd /home/archipelago/archy && git fetch origin main && git reset --hard origin/main
+          REPO_DIR="$HOME/archy"
+          cd "$REPO_DIR" && git fetch origin main && git reset --hard origin/main
           echo "=== Source at commit: $(git log --oneline -1) ==="
           rsync -a --delete \
             --exclude '.git' --exclude 'node_modules' --exclude 'target' \
             --exclude 'image-recipe/build' --exclude 'image-recipe/results' \
             --exclude 'web/dist' \
-            /home/archipelago/archy/ "$GITHUB_WORKSPACE/"
+            "$REPO_DIR/" "$GITHUB_WORKSPACE/"
           cd "$GITHUB_WORKSPACE"
           echo "=== Workspace version: $(grep '^version' core/archipelago/Cargo.toml) ==="
           [ -f "scripts/first-boot-containers.sh" ] && echo "  first-boot-containers.sh: PRESENT" || echo "  first-boot-containers.sh: MISSING"

.gitea/workflows/build-iso.yml

@@ -13,11 +13,12 @@ jobs:
       - name: Checkout
         run: |
           # Direct clone using stored credentials (actions/checkout token is broken)
-          cd /home/archipelago/archy && git fetch origin main && git reset --hard origin/main
+          REPO_DIR="$HOME/archy"
+          cd "$REPO_DIR" && git fetch origin main && git reset --hard origin/main
           echo "=== Source at commit: $(git log --oneline -1) ==="
           echo "=== Syncing to workspace ==="
           rsync -a --delete --exclude='.git' --exclude='target/' --exclude='node_modules/' \
-            /home/archipelago/archy/ "$GITHUB_WORKSPACE/" || cp -a /home/archipelago/archy/* "$GITHUB_WORKSPACE/"
+            "$REPO_DIR/" "$GITHUB_WORKSPACE/" || cp -a "$REPO_DIR"/* "$GITHUB_WORKSPACE/"
           cd "$GITHUB_WORKSPACE"
           echo "=== Workspace version: $(grep '^version' core/archipelago/Cargo.toml) ==="
           echo "=== Key files ==="
@@ -45,7 +46,7 @@ jobs:
         run: |
           WORK_DIR="image-recipe/build/auto-installer"
           mkdir -p "$WORK_DIR"
-          CACHED="/home/archipelago/archy/image-recipe/build/auto-installer/debian-live-installer.iso"
+          CACHED="$HOME/archy/image-recipe/build/auto-installer/debian-live-installer.iso"
           if [ -f "$CACHED" ] && [ ! -f "$WORK_DIR/debian-live-installer.iso" ]; then
             cp "$CACHED" "$WORK_DIR/debian-live-installer.iso"
             echo "Cached Debian Live ISO copied ($(du -h "$WORK_DIR/debian-live-installer.iso" | cut -f1))"