chore(style): codebase em-dash sweep + minor layout polish

Replaces every em-dash and en-dash with regular ASCII hyphens
across comments, JSX strings, and dev-facing logs. Mostly cosmetic
but stops the inconsistent mix that crept in over the last few
months (some files used em-dashes in comments, others didn't,
some used both).

Bundles two small dashboard-layout tweaks that touch a couple of
already-modified files:
- (dashboard)/layout.tsx main padding goes from p-6 to pt-3 px-6
  pb-6 so page content sits closer to the topbar.
- Sidebar now receives the ports list it needs for the footer
  port switcher.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/yachts/yacht-card.tsx

@@ -40,12 +40,12 @@ export function YachtCard({ yacht, portSlug, onEdit, onArchive }: YachtCardProps
   // Prefer metric dimensions; fall back to imperial
   let dimText: string | null = null;
   if (yacht.lengthM || yacht.widthM) {
-    const l = yacht.lengthM ?? '—';
-    const w = yacht.widthM ?? '—';
+    const l = yacht.lengthM ?? '-';
+    const w = yacht.widthM ?? '-';
     dimText = `${l}m × ${w}m`;
   } else if (yacht.lengthFt || yacht.widthFt) {
-    const l = yacht.lengthFt ?? '—';
-    const w = yacht.widthFt ?? '—';
+    const l = yacht.lengthFt ?? '-';
+    const w = yacht.widthFt ?? '-';
     dimText = `${l}ft × ${w}ft`;
   }