initial: split from gov-agreg — vreau.digital standalone platform

Moved from gov-agreg/src/pages/achizitii/* to root (drop prefix).
- 22 pages migrated, 127 files total
- All internal links: /achizitii/X → /X (176 occurrences fixed)
- AchizitiiLayout subnav rewritten: /X paths, top-right link to vreaudigital.ro hub
- BaseLayout new (vreau.digital branding, OG tags, site URL)
- astro.config.mjs: site https://vreau.digital, server output (was static)
- docker-compose: port 5096 (vreaudigital is 5095), container vreau-digital
- deploy.sh: paths /opt/vreau-digital, log /var/log/vreau-digital-deploy.log

Backend shared with gov-agreg:
- PostgreSQL satra (same schemas: seap, firms, anaf, anre, ...)
- Photon, Martin tiles
- Infisical /vreaudigital path (DATABASE_URL etc. shared)

build: PASS (npx astro check 0 errors, npm run build 5s vite + 10s server)

src/lib/supabase.ts

@@ -0,0 +1,15 @@
+import { createClient } from '@supabase/supabase-js';
+
+const supabaseUrl = import.meta.env.PUBLIC_SUPABASE_URL || process.env.PUBLIC_SUPABASE_URL || '';
+const supabaseAnonKey = import.meta.env.PUBLIC_SUPABASE_ANON_KEY || process.env.PUBLIC_SUPABASE_ANON_KEY || '';
+
+export const supabaseEnabled = !!(supabaseUrl && supabaseAnonKey);
+
+export const supabase = supabaseEnabled
+  ? createClient(supabaseUrl, supabaseAnonKey)
+  : null;
+
+export function getSupabaseClient() {
+  if (!supabase) throw new Error('Supabase not configured');
+  return supabase;
+}