feat(distribution): production install/update/backup scripts + public-repo sync (#106)

Builds the customer-facing distribution: a curated distribution/ directory
containing only what an end customer needs (production docker-compose.yml
with no build: sections, install.sh/update.sh/uninstall.sh/healthcheck.sh/
backup.sh/restore.sh, a customer-facing CHANGELOG.md, and README/LICENSE/
NOTICE/THIRD_PARTY_LICENSES) — pushed as the initial content of the new
public alleyviper/argus repo.

install.sh: detects OS, validates Docker/Compose, fetches all deployment
files, generates a secure DB password, creates the required Docker
network, pulls images, starts the stack, waits for health, and rotates
the default admin/admin credentials via the auth API — printing the
generated password once at the end.

update.sh/healthcheck.sh/backup.sh/restore.sh/uninstall.sh formalize what
was previously ad-hoc README snippets into real, safe-by-default scripts
(uninstall.sh keeps data unless --remove-data is explicitly passed and
confirmed; restore.sh requires typed confirmation and documents that it
targets a fresh install, not a live merge).

Added a sync-distribution job to release.yml: after a successful release,
mirrors distribution/ into the public repo and creates a matching
(customer-facing, commit-log-free) release marker there. Needs a one-time
setup step — a fine-grained PAT scoped to alleyviper/argus added as the
ARGUS_PUBLIC_REPO_TOKEN secret — the job cleanly no-ops until that's added.

Not yet done: GHCR package visibility (argus-secure-api/-ui/-nginx) is
still private, which blocks a genuine end-to-end curl-install test from a
clean, unauthenticated environment — deferred at the user's request until
they flip it manually (GitHub does not expose this via API).

uninstall.sh

@@ -0,0 +1,59 @@
+#!/usr/bin/env bash
+#
+# ARGUS uninstaller — stops and removes ARGUS containers.
+#
+# By default this KEEPS your data (database, certificates, uploaded config) —
+# it only stops and removes containers, so a plain re-install (install.sh)
+# picks up right where you left off.
+#
+#   cd ~/argus && ./uninstall.sh                  # containers only, data kept
+#   ./uninstall.sh --remove-data                  # also destroys all data (asks to confirm)
+#   ./uninstall.sh --remove-data --yes             # non-interactive, for scripted use
+#
+set -euo pipefail
+
+INSTALL_DIR="${ARGUS_INSTALL_DIR:-$HOME/argus}"
+REMOVE_DATA=false
+ASSUME_YES=false
+
+for arg in "$@"; do
+  case "$arg" in
+    --remove-data) REMOVE_DATA=true ;;
+    --yes|-y)      ASSUME_YES=true ;;
+    *) echo "Unknown option: $arg" >&2; exit 1 ;;
+  esac
+done
+
+bold()  { printf '\033[1m%s\033[0m\n' "$1"; }
+info()  { printf '  %s\n' "$1"; }
+ok()    { printf '  \033[32m✓\033[0m %s\n' "$1"; }
+warn()  { printf '  \033[33m!\033[0m %s\n' "$1"; }
+fail()  { printf '  \033[31m✗\033[0m %s\n' "$1" >&2; exit 1; }
+
+bold "ARGUS Uninstaller"
+echo
+
+[ -f "$INSTALL_DIR/docker-compose.yml" ] || fail "No ARGUS installation found at $INSTALL_DIR (set ARGUS_INSTALL_DIR if you installed elsewhere)."
+cd "$INSTALL_DIR"
+
+if [ "$REMOVE_DATA" = "true" ] && [ "$ASSUME_YES" != "true" ]; then
+  warn "This will permanently delete your ARGUS database, certificates, and all"
+  warn "uploaded configuration. This cannot be undone."
+  printf "  Type YES to confirm: "
+  read -r CONFIRM
+  [ "$CONFIRM" = "YES" ] || fail "Aborted — data was not touched."
+fi
+
+if [ "$REMOVE_DATA" = "true" ]; then
+  bold "Stopping ARGUS and removing all data..."
+  docker compose down -v
+  ok "Containers and data volumes removed"
+else
+  bold "Stopping ARGUS (data preserved)..."
+  docker compose down
+  ok "Containers removed — database and certificates are untouched"
+  info "Re-run install.sh (or 'docker compose up -d' here) to bring ARGUS back with the same data."
+fi
+
+echo
+info "Configuration files remain at ${INSTALL_DIR} — remove that directory yourself if you want a completely clean slate."