refactor: remove dead code — orphaned files, unused types and functions

Delete 3 orphaned files (SubNav, TopBar, problems.ts), remove 4 unused
type definitions from pmr.ts (ViewId, NavItem, ReferralFormData, Problem),
trim types/index.ts to only Phase, and remove unused utility functions
(calculateSkillOffset, formatBootLine, getProfileContent, DotColorName).

src/lib/utils.ts

@@ -1,12 +1,3 @@
-export function calculateSkillOffset(level: number, radius: number): number {
-  const circumference = 2 * Math.PI * radius
-  return circumference * (1 - level / 100)
-}
-
-export function formatBootLine(text: string): string {
-  return text
-}
-
 export function hexToRgba(hex: string, opacity: number): string {
   const r = parseInt(hex.slice(1, 3), 16)
   const g = parseInt(hex.slice(3, 5), 16)