Remove hardcoded .bmad folder references throughout documentation and source files, replacing them with the configurable {bmad_folder} placeholder. This change enables users to customize the BMAD installation folder name via configuration, improving flexibility and reducing coupling to a specific directory structure.
Changes include:
- Update all documentation to reference {bmad_folder} instead of .bmad
- Remove legacy configuration files from .bmad and .claude directories
- Update workflow.xml and CLI documentation with new placeholder syntax
