Phase 1: Monorepo scaffold, database, and dev environment

Turborepo monorepo with @forte/shared and @forte/backend workspaces.
Docker Compose dev env with PostgreSQL 16 + Valkey 8.
Fastify server with Pino JSON logging, request ID tracing, and
health endpoint. Drizzle ORM with company + location tables.

Includes:
- Root config (turbo, tsconfig, eslint, prettier)
- @forte/shared: types, schemas, currency/date utils
- @forte/backend: Fastify entry, plugins (database, redis, cors,
  error-handler, dev-auth), health route, Drizzle schema + migration
- Dev auth bypass via X-Dev-Company/Location/User headers
- Vitest integration test with clean DB per test (forte_test)
- Seed script for dev company + location

turbo.json

@@ -0,0 +1,20 @@
+{
+  "$schema": "https://turbo.build/schema.json",
+  "tasks": {
+    "dev": {
+      "cache": false,
+      "persistent": true
+    },
+    "build": {
+      "dependsOn": ["^build"],
+      "outputs": ["dist/**"]
+    },
+    "test": {
+      "dependsOn": ["^build"],
+      "cache": false
+    },
+    "lint": {
+      "dependsOn": ["^build"]
+    }
+  }
+}