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/hooks/use-is-mobile.ts

@@ -7,7 +7,7 @@ const MOBILE_QUERY = '(max-width: 1023.98px)';
 /**
  * Returns true when the viewport is below the `lg` Tailwind breakpoint.
  * Backed by a media-query listener; safe to call from any client component.
- * Server renders return `false` (desktop default) — clients hydrate to the
+ * Server renders return `false` (desktop default) - clients hydrate to the
  * true viewport state on mount.
  *
  * Not unit-tested: the repo's vitest is configured for environment='node'