feat: post composition redesign + budget allocation + brand identity (Rawaj)

Post Workflow:
- PostDetail full page (/posts/:id) replaces slide panel approach
- Post = 1 Caption Copy + 1 Body Copy + 1 Design + 0-1 Video
- copy_type field on Translations (caption/body)
- Composition endpoint returns rich data (content preview, languages, thumbnails)
- Stage auto-advances on translation/artefact changes (both link and unlink)
- "Translations" renamed to "Copy" in navigation
- GET /api/posts/:id, /api/translations/:id, /api/artefacts/:id routes added
- PostProduction: "New Post" creates → navigates to full page
- CampaignDetail: click post → navigates to full page
- Inline link picker (no modals) with search + rich item display
- PostComposition sub-components for caption, copy, designs, video, formats, readiness

Budget Allocation:
- Single source of truth: BudgetEntries (Campaign.budget deprecated)
- Budget mutex for race conditions
- Validation at all levels (main → campaign → track, expenses)
- CEO approval workflow: BudgetRequests table, public approval page
- Finance page: request budget UI, budget requests section
- Settings: CEO email field
- All emails branded with "Rawaj —" prefix

Brand Identity:
- Name: Rawaj (رواج) — trending/virality
- Deep teal palette (#0d9488), forest-tinted dark mode
- DM Sans font, custom SVG logo
- Consistent across login, sidebar, emails, public pages

Approval Workflow:
- Single reviewer per artefact (not multi-select)
- Reviewer redirect on public review page
- Server blocks submit-review without reviewer
- Review URLs use APP_URL (not server URL)

UI/UX:
- Scroll clipping fix: Modal, TabbedModal, SlidePanel restructured
  to avoid overflow-y-auto clipping native select dropdowns
- section-card overflow-hidden → overflow-clip
- All page titles via Header.jsx (removed duplicate h1s)
- CampaignDetail redesigned: prominent budget card, compact team

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

client/src/utils/platformFormats.js

@@ -0,0 +1,39 @@
+export const PLATFORM_FORMATS = {
+  instagram: [
+    { key: 'ig_feed', label: 'Feed (1:1)', ratio: '1:1' },
+    { key: 'ig_story', label: 'Story (9:16)', ratio: '9:16' },
+    { key: 'ig_reel', label: 'Reel (9:16)', ratio: '9:16' },
+  ],
+  tiktok: [
+    { key: 'tt_video', label: 'TikTok (9:16)', ratio: '9:16' },
+  ],
+  youtube: [
+    { key: 'yt_video', label: 'YouTube (16:9)', ratio: '16:9' },
+    { key: 'yt_short', label: 'Short (9:16)', ratio: '9:16' },
+    { key: 'yt_thumb', label: 'Thumbnail (16:9)', ratio: '16:9' },
+  ],
+  facebook: [
+    { key: 'fb_post', label: 'Post (1:1)', ratio: '1:1' },
+    { key: 'fb_story', label: 'Story (9:16)', ratio: '9:16' },
+  ],
+  twitter: [
+    { key: 'tw_post', label: 'Post (16:9)', ratio: '16:9' },
+  ],
+  linkedin: [
+    { key: 'li_post', label: 'Post (1:1)', ratio: '1:1' },
+  ],
+  snapchat: [
+    { key: 'sc_snap', label: 'Snap (9:16)', ratio: '9:16' },
+  ],
+}
+
+export function getFormatsForPlatforms(platforms = []) {
+  const formats = []
+  const seen = new Set()
+  for (const p of platforms) {
+    for (const f of (PLATFORM_FORMATS[p] || [])) {
+      if (!seen.has(f.key)) { seen.add(f.key); formats.push(f) }
+    }
+  }
+  return formats
+}