docs(README): update installation instructions for various distributions

Makefile

@@ -1,8 +1,8 @@
 BINARY     := unitdore
-INSTALL_DIR := /usr/local/bin
+INSTALL_DIR := /usr/bin
 CONFIG_DIR  := /etc/unitdore
 VERSION    := $(shell git describe --tags --always --dirty 2>/dev/null || echo "dev")
-LDFLAGS    := -ldflags "-X main.version=$(VERSION)"
+LDFLAGS    := -ldflags "-X github.com/warkanum/unitdore/cmd.version=$(VERSION)"
 
 .PHONY: all build install uninstall test lint clean release-version
 
@@ -42,17 +42,23 @@ lint:
 clean:
 	rm -f $(BINARY)
 
-## release-version: bump patch version, tag, and push to trigger release workflow
+## release-version: bump patch version, update source versions, commit, tag, and push
 release-version:
 	@CURRENT=$$(git describe --tags --abbrev=0 2>/dev/null || echo "v0.0.0"); \
 	MAJOR=$$(echo $$CURRENT | sed 's/v\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1/'); \
 	MINOR=$$(echo $$CURRENT | sed 's/v\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\2/'); \
 	PATCH=$$(echo $$CURRENT | sed 's/v\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\3/'); \
 	NEXT="v$$MAJOR.$$MINOR.$$((PATCH + 1))"; \
+	PKGVER="$$MAJOR.$$MINOR.$$((PATCH + 1))"; \
 	echo "Current: $$CURRENT → Next: $$NEXT"; \
+	sed -i "s/^var version = .*/var version = \"$$PKGVER\"/" cmd/root.go; \
+	sed -i "s/^pkgver=.*/pkgver=$$PKGVER/" pkg/arch/PKGBUILD; \
+	sed -i "s/^Version:.*/Version:        $$PKGVER/" pkg/centos/unitdore.spec; \
+	git add cmd/root.go pkg/arch/PKGBUILD pkg/centos/unitdore.spec; \
+	git commit -m "chore(release): update package version to $$PKGVER"; \
 	git tag -a "$$NEXT" -m "Release $$NEXT"; \
-	git push origin "$$NEXT"; \
-	echo "Pushed tag $$NEXT — release workflow triggered"
+	git push origin HEAD "$$NEXT"; \
+	echo "Pushed $$NEXT — release workflow triggered"
 
 ## help: show this help
 help: