Modify Makefile to increment major version when PROXYSQLGENAI is enabled

When PROXYSQLGENAI=1 is set, the major version number in GIT_VERSION
is incremented by 1. For example:
- 3.0.6-386-g79756e7 becomes 4.0.6-386-g79756e7
- 2.7.1-123-abc1234 becomes 3.7.1-123-abc1234

This allows distinguishing GenAI-enabled builds from standard builds
through the version string.

Makefile

@@ -13,6 +13,12 @@ GIT_VERSION ?= $(shell git describe --long --abbrev=7 2>/dev/null || git describ
 ifndef GIT_VERSION
     $(error GIT_VERSION is not set)
 endif
+
+# If PROXYSQLGENAI is enabled, increment the major version number by 1
+ifeq ($(PROXYSQLGENAI),1)
+    GIT_VERSION := $(shell echo "$(GIT_VERSION)" | awk -F. '{printf "%d.%s", $$1+1, substr($$0, length($$1)+2)}')
+endif
+
 export GIT_VERSION
 
 ### NOTES: