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/admin/ocr-settings-form.tsx

@@ -160,7 +160,7 @@ function SettingsBlock({ scope, title, description, showUseGlobal }: SettingsBlo
                 Enable AI receipt parsing for this port
               </Label>
               <p className="text-xs text-muted-foreground">
-                Off by default. Receipts are read on-device using Tesseract.js — accurate enough for
+                Off by default. Receipts are read on-device using Tesseract.js - accurate enough for
                 most receipts and incurs no AI cost. Turning this on lets the configured provider
                 re-parse receipts server-side for higher accuracy on hard-to-read images.
               </p>
@@ -214,7 +214,7 @@ function SettingsBlock({ scope, title, description, showUseGlobal }: SettingsBlo
               id={`apiKey-${scope}`}
               type={showKey ? 'text' : 'password'}
               autoComplete="off"
-              placeholder={hasKey ? '•••••• (saved — leave blank to keep)' : 'sk-…'}
+              placeholder={hasKey ? '•••••• (saved - leave blank to keep)' : 'sk-…'}
               value={apiKey}
               onChange={(e) => {
                 setApiKey(e.target.value);