Add publishing scripts and release assets

- Add publish.ps1 and build-release.ps1 for publishing to Gitea
- Add dockmv logo assets (full, small, very small variants)
- Update Makefile with publish and publish-binaries targets
- Support PowerShell-based release pipeline with Gitea integration

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

Makefile

@@ -3,15 +3,23 @@ LDFLAGS := -s -w -X main.version=$(VERSION)
 BIN     := docker-migrate
 OUT     := dist
 
-.PHONY: all ui build run test vet fmt docker clean release help
+# PowerShell 7+. The publish path lives in scripts/*.ps1 because uploading a
+# Gitea release asset needs an HTTP client, not a shell loop.
+PWSH ?= pwsh
+# Extra flags forwarded to publish.ps1, e.g. `make publish ARGS=-Force`.
+ARGS ?=
+
+.PHONY: all ui build run test vet fmt docker clean release publish publish-binaries help
 
 help:
-	@echo "make ui       build the web interface into internal/webui/dist"
-	@echo "make build    build the binary for this platform (implies ui)"
-	@echo "make run      build and start the server on 127.0.0.1:8080"
-	@echo "make test     run the Go tests"
-	@echo "make docker   build the container image"
-	@echo "make release  cross-compile linux/amd64, linux/arm64, darwin/arm64, windows/amd64"
+	@echo "make ui                build the web interface into internal/webui/dist"
+	@echo "make build             build the binary for this platform (implies ui)"
+	@echo "make run               build and start the server on 127.0.0.1:8080"
+	@echo "make test              run the Go tests"
+	@echo "make docker            build the container image"
+	@echo "make release           cross-compile linux/amd64, linux/arm64, darwin/arm64, windows/amd64"
+	@echo "make publish           push the image to git.azuze.fr and attach binaries to the release"
+	@echo "make publish-binaries  binaries only: no docker build, login or push"
 
 all: build
 
@@ -52,6 +60,16 @@ release: ui
 	done
 	@ls -lh $(OUT)
 
+# Needs GITEA_USER + GITEA_TOKEN in the environment, or it prompts. The token
+# needs package read/write for the push and write:repository for the release.
+publish:
+	$(PWSH) -NoProfile -ExecutionPolicy Bypass -File scripts/publish.ps1 \
+	  -Tag $(VERSION) -PublishRelease $(ARGS)
+
+publish-binaries:
+	$(PWSH) -NoProfile -ExecutionPolicy Bypass -File scripts/publish.ps1 \
+	  -Tag $(VERSION) -BinariesOnly $(ARGS)
+
 clean:
 	rm -rf $(BIN) $(BIN).exe $(OUT) internal/webui/dist/assets
 	rm -rf web/node_modules