Add Go workspace for multi-module development.

This allows nested modules to reference the root prometheus/prometheus
module from the local filesystem instead of downloading versioned
releases. Improves development workflow and ensures CI tests against
current code.

Signed-off-by: Julien Pivotto <291750+roidelapluie@users.noreply.github.com>

.gitignore

@@ -26,6 +26,7 @@ npm_licenses.tar.bz2
 
 /vendor
 /.build
+/go.work.sum
 
 /**/node_modules
 

Makefile

@@ -194,6 +194,8 @@ GO_SUBMODULE_DIRS := documentation/examples/remote_storage internal/tools web/ui
 .PHONY: update-all-go-deps
 update-all-go-deps: update-go-deps
 	$(foreach dir,$(GO_SUBMODULE_DIRS),$(MAKE) update-go-deps-in-dir DIR=$(dir);)
+	@echo ">> syncing Go workspace"
+	@$(GO) work sync
 
 .PHONY: update-go-deps-in-dir
 update-go-deps-in-dir:

go.work

@@ -0,0 +1,8 @@
+go 1.24.9
+
+use (
+	.
+	./documentation/examples/remote_storage
+	./internal/tools
+	./web/ui/mantine-ui/src/promql/tools
+)