Add MCR registry tagging and push target to Makefile

Add MCR variable. Replace local mcias:VERSION tags with MCR registry
URL. Remove :latest tag. Add push target.

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

Makefile

@@ -20,6 +20,7 @@
 # Variables
 # ---------------------------------------------------------------------------
 MODULE     := git.wntrmute.dev/mc/mcias
+MCR        := mcr.svc.mcp.metacircular.net:8443
 BINARIES   := mciassrv mciasctl mciasdb mciasgrpcctl
 BIN_DIR    := bin
 MAN_DIR    := man/man1
@@ -163,9 +164,12 @@ dist: man
 # ---------------------------------------------------------------------------
 # docker — build the Docker image
 # ---------------------------------------------------------------------------
-.PHONY: docker
+.PHONY: docker push
 docker:
-	docker build --force-rm -t mcias:$(VERSION) -t mcias:latest .
+	docker build --force-rm -t $(MCR)/mcias:$(VERSION) .
+
+push: docker
+	docker push $(MCR)/mcias:$(VERSION)
 
 # ---------------------------------------------------------------------------
 # docker-clean — remove local mcias Docker images

flake.nix

@@ -10,7 +10,7 @@
     let
       system = "x86_64-linux";
       pkgs = nixpkgs.legacyPackages.${system};
-      version = "1.7.0";
+      version = "1.8.0";
     in
     {
       packages.${system} = {