Implement a mandatory State Machine model (PLAN and IMPLEMENTATION states)
in root instructions to prevent the AI from generating code prematurely.
The rules require mechanical reloading of skill files during execution
to combat context-window memory loss.
Also update Mermaid diagram instructions to explicitly ban <br> tags for
newlines and prohibit raw angle brackets (<, >) in nodes, enforcing
real newlines and HTML entities (<, >) to fix rendering issues.
The \n literal often fails to render correctly in Mermaid nodes. The
guidelines now require using actual newlines inside quoted text to
ensure multiline content displays reliably.
