Insert urgent work between phases

Insert urgent decimal phase between existing planned phases

Handling urgent work discovered mid-milestone without renumbering the entire roadmap.

• · After phase number (e.g., 72) and description for new phase

• · Decimal phase number (e.g., 72.1, 72.2)
• · Updated ROADMAP.md with new phase
• · Updated STATE.md with insertion logged

• · insert-phase.md workflow

• · ROADMAP.md exists with integer phases
• · After phase exists in roadmap
• · .planning/ directory structure intact

• · After phase not found → error reported
• · ROADMAP.md malformed → parsing fails
• · Decimal phase already exists → conflict detected

• · Preserves logical sequence of integer phases
• · Decimal naming avoids roadmap scramble
• · STATE.md logs insertion for audit trail