docs: Add AGENTS.md guide and enhance extras documentation

Complete AI agent guide with quick start, architecture overview, coding
principles (KISS/DRY), and enhanced extras module documentation.

Fixes #595 🦕

Signed-off-by: Emmanuel Hugonnet <ehugonne@redhat.com>

Author: ehsavoie

.gitignore

@@ -41,6 +41,7 @@ nb-configuration.xml
 
 # Plugin directory
 /.quarkus/cli/plugins/
+
 # TLS Certificates
 .certs/
 
@@ -49,6 +50,7 @@ nbproject/
 nbactions.xml
 
 # Private Claude config
+.bob
 .claude/
 .serena/
 claudedocs