Initial release: self-hostable APT repository server and CLI

urapt is a self-hostable APT repository server with a companion CLI for
pushing and managing Debian .deb packages.

Server (urapt-server):
- REST API + APT endpoint, SQLite storage (pure-Go modernc driver, no CGO)
- .deb files stored content-addressed on disk, reference-counted for dedup
- Server-managed RSA-4096 OpenPGP signing key (ProtonMail/go-crypto)
- APT indices (Release/InRelease/Packages[.gz/.xz]) generated on demand
  from the DB, cached in memory, signed with the server key
- Full APT model: repositories -> distributions -> components -> architectures
- Bearer-token auth for REST; HTTP Basic auth for private-repo APT reads
- First registrant becomes admin; repo-scoped permissions
  (read/write/read-write/admin) plus owner and server-admin roles
- Multipart package push with control-field extraction, list/show/delete,
  pool serving, blob ref-count cleanup
- Audit log

CLI (urapt):
- register/login/logout/whoami, token management
- repo/distro/component/arch CRUD, member management
- push/pull/ls/show/rm for packages
- apt-config helper that emits apt setup commands (key, sources.list,
  auth.conf for private repos)

Packaging & docs:
- Dockerfile (multi-stage distroless), docker-compose.yml, sample config
- README quick start, architecture overview, config reference, security notes
- PLAN.md design blueprint, CHANGELOG.md, GPL-3.0 LICENSE
- GitHub Actions CI (test, lint, cross-build for linux/darwin amd64/arm64)
- Makefile release target producing static binaries + tarballs + checksums

Tests cover the data-access layer, auth/permission checks, APT index
generation, .deb parsing, GPG signing, the REST API, and the typed API
client. Verified end-to-end on a Raspberry Pi (arm64) pushing and installing
a real package.

cmd/urapt-server/main.go

@@ -0,0 +1,22 @@
+// Package main is the urapt-server entrypoint.
+package main
+
+import (
+	"context"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"urapt/server/app"
+	"urapt/shared/version"
+)
+
+func main() {
+	a := app.New(os.Args[1:], version.Version)
+	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
+	defer stop()
+
+	if err := a.Run(ctx); err != nil {
+		os.Exit(1)
+	}
+}

cmd/urapt/main.go

@@ -0,0 +1,15 @@
+// Package main is the urapt CLI entrypoint.
+package main
+
+import (
+	"os"
+
+	"urapt/cli/commands"
+	"urapt/shared/version"
+)
+
+func main() {
+	if err := commands.New(version.Version).Execute(os.Args[1:]); err != nil {
+		os.Exit(1)
+	}
+}