feat(db): add Prisma schema and global PrismaModule

Models mirror Hiboutik entities (categories tree, brands, suppliers, products and their versions, customers) plus addresses and orders for the upcoming sync. Every synced model is matched with Hiboutik through a unique hiboutikId. The generated client is ignored by git and env files other than .env.example are ignored.

.gitignore

@@ -37,10 +37,8 @@ lerna-debug.log*
 
 # dotenv environment variable files
 .env
-.env.development.local
-.env.test.local
-.env.production.local
-.env.local
+.env.*
+!.env.example
 
 # temp directory
 .temp
@@ -54,3 +52,6 @@ pids
 
 # Diagnostic reports (https://nodejs.org/api/report.html)
 report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json
+
+# Prisma client (regenerated by `prisma generate`, run on npm install)
+/prisma/generated/