refactor(packaging): split into dispatch/dispatch-systemd/dispatch-s6, separate dispatch-electron, add bun-based frontend serve

PKGBUILD is now a split package producing three .pkg.tar.zst files in one
makepkg run:
  - dispatch          base application files (/opt/dispatch), CLI wrappers
                       (dispatch-api, dispatch-frontend), env configs
                       (/etc/dispatch/dispatch-api.conf,
                        /etc/dispatch/dispatch-frontend.conf)
  - dispatch-systemd  systemd user units for dispatch-api + dispatch-frontend
                       (conflicts with dispatch-s6)
  - dispatch-s6       s6-rc service pipelines (-srv + -log) for both services
                       (conflicts with dispatch-systemd)

The Electron desktop wrapper moved to its own self-contained PKGBUILD at
packaging/electron/, producing dispatch-electron. It bundles its own copy of
the frontend dist + electron entry points under /opt/dispatch-electron and
does not depend on the base dispatch package, so users can install it
standalone and point VITE_API_URL at any backend at build time.

Files under packaging/ are now read directly from ${_projectdir}/packaging/
rather than via source=(); the two s6 service dirs share basenames (run,
type) which would collide inside ${srcdir}.

New frontend static server: packages/frontend/serve.ts uses Bun's built-in
HTTP server (no extra runtime deps) with SPA fallback to index.html and
path-traversal protection. PORT/HOST/DIST_DIR overridable via env. Exposed
as 'bun run --cwd packages/frontend serve' and via /usr/bin/dispatch-frontend.

Build scripts:
  - bin/build-pkg            now prints the freshest built packages
  - bin/install-pkg          installs dispatch + dispatch-systemd by default;
                              accepts package names or --all; searches both
                              packaging/ and packaging/electron/
  - bin/build-pkg-electron   new, builds the electron split
  - bin/build-pkg-windows    replaces bin/windows-pkg; drops the hard-coded
                              WSL copy step, just prints the win-unpacked path

.gitignore extended to cover packaging/*.tar.zst and packaging/electron/{src,pkg,*.pkg.tar.zst,*.tar.zst}.

1 files changed, 21 insertions, 0 deletions

diff --git a/packaging/dispatch-frontend.conf b/packaging/dispatch-frontend.conf
new file mode 100644
index 0000000..37d2984
--- /dev/null
+++ b/packaging/dispatch-frontend.conf
@@ -0,0 +1,21 @@
+# /etc/dispatch/dispatch-frontend.conf
+# Environment configuration for the Dispatch Frontend static-file server.
+# Sourced by systemd (EnvironmentFile=), the s6 run script, and the
+# dispatch-frontend-wrapper.sh script for manual invocation.
+#
+# Lines beginning with '#' are comments and are ignored.
+# Syntax: KEY=value  (no spaces around '=', no 'export' keyword needed for systemd)
+
+# ---------------------------------------------------------------------------
+# Server
+# ---------------------------------------------------------------------------
+
+# Port the static file server listens on (default: 18391).
+PORT=18391
+
+# Interface to bind to (default: 0.0.0.0).
+# HOST=0.0.0.0
+
+# Directory containing the built frontend assets.
+# Defaults to /opt/dispatch/packages/frontend/dist
+# DIST_DIR=/opt/dispatch/packages/frontend/dist