feat(installer): update install messages for Beta.0 release

tools/cli/installers/install-messages.yaml

@@ -6,18 +6,16 @@
 startMessage: |
   ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
 
-  🎉 BETA IS HERE! Welcome to BMad Method Beta.0!
+  🎉 BETA IS HERE! Welcome to BMad Method V6 Beta!
 
   We've officially graduated from Alpha! This milestone represents:
-    - 21+ production-ready agents
     - 50+ workflows covering the full development lifecycle
-    - Windows compatibility (via @clack/prompts)
-    - Module ecosystem with separate repos for focused development
-
-  If upgrading from Alpha: Remove .bmad folder for a fresh start.
+    - Stability - we will still be adding and evolving and optimizing, 
+      but anticipate no massive breaking changes
+    - Groundwork in place for customization and community modules
 
   📚 New Docs Site: http://docs.bmad-method.org/
-    - Tons of guides and articles coming soon!
+    - High quality tutorials, guided walkthrough, and articles coming soon!
     - Everything is free. No paywalls. No gated content.
     - Knowledge should be shared, not sold.
 
@@ -25,7 +23,7 @@ startMessage: |
     - GitHub: https://github.com/bmad-code-org/BMAD-METHOD/
     - YouTube: https://www.youtube.com/@BMadCode
 
-  Latest updates: https://github.com/bmad-code-org/BMAD-METHOD/blob/main/CHANGELOG.md
+  Latest updates: https://github.com/bmad-code-org/BMAD-METHOD/CHANGELOG.md
 
   ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
 
@@ -33,13 +31,14 @@ startMessage: |
 endMessage: |
   ════════════════════════════════════════════════════════════════════════════════
 
-  ✨ BMAD BETA IS READY! Thank you for being part of this journey!
+  ✨ BMAD V6 BETA IS INSTALLED! Thank you for being part of this journey!
 
   🌟 BMad is 100% free and open source.
     - No gated Discord. No paywalls.
     - We believe in empowering everyone, not just those who can pay.
 
   🙏 SUPPORT BMAD DEVELOPMENT:
+    - During the Beta, please give us feedback and raise issues on GitHub!
     - Donate: https://buymeacoffee.com/bmad
     - Corporate Sponsorship available - DM on Discord
 
@@ -50,7 +49,7 @@ endMessage: |
 
   📚 RESOURCES:
     - Docs: http://docs.bmad-method.org/ (bookmark it!)
-    - Changelog: https://github.com/bmad-code-org/BMAD-METHOD/blob/main/CHANGELOG.md
+    - Changelog: https://github.com/bmad-code-org/BMAD-METHOD/CHANGELOG.md
 
   ⭐⭐⭐ HELP US GROW:
     - Star us on GitHub: https://github.com/bmad-code-org/BMAD-METHOD/