chore: bump version to 6.3.1-alpha.23

Ready for npm publish and installation with:
- GSDMAD v2.0 multi-agent pipeline
- Improved batch-super-dev workflow (stories first, then mode)
- Implementation readiness check
- Backlog story support

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "@jonahschulte/bmad-method",
-  "version": "6.4.0-alpha.0",
+  "version": "6.3.1-alpha.23",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@jonahschulte/bmad-method",
-      "version": "6.4.0-alpha.0",
+      "version": "6.3.1-alpha.23",
       "license": "MIT",
       "dependencies": {
         "@clack/prompts": "^0.11.0",

package.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://json.schemastore.org/package.json",
   "name": "@jonahschulte/bmad-method",
-  "version": "6.3.0-alpha.23",
+  "version": "6.3.1-alpha.23",
   "description": "Breakthrough Method of Agile AI-driven Development (Enhanced with hospital-grade quality, TDD, and intelligent multi-agent review)",
   "keywords": [
     "agile",