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/documents/document-detail.tsx

@@ -174,7 +174,7 @@ export function DocumentDetail({ documentId, portSlug }: DocumentDetailProps) {
         data: { to: string[]; subject: string; attachments: Array<{ fileId: string }> };
       }>(`/api/v1/documents/${documentId}/compose-completion-email`, { method: 'POST' });
       toast.info(
-        `Email composer prepared for ${draft.data.to.length} signer${draft.data.to.length === 1 ? '' : 's'} — opens in PR8 wizard`,
+        `Email composer prepared for ${draft.data.to.length} signer${draft.data.to.length === 1 ? '' : 's'} - opens in PR8 wizard`,
       );
     } catch (err) {
       toast.error(err instanceof Error ? err.message : 'Failed to prepare email');