implement foundation + room system (Plan 1 of 5)

Bun workspace monorepo with shared, server, client packages.
Server: Hono + @hono/node-ws, Drizzle + PostgreSQL, in-memory room manager
with WebSocket broadcasting, HTTP room creation, DB persistence layer.
Client: React 19 + Vite + Tailwind v4 + shadcn/ui, TanStack Router with
landing/display/host/player routes, Zustand store, WebSocket connection hook.
20 tests passing (room manager unit + WS integration).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

biome.json

@@ -0,0 +1,24 @@
+{
+	"$schema": "https://biomejs.dev/schemas/latest/schema.json",
+	"organizeImports": {
+		"enabled": true
+	},
+	"formatter": {
+		"enabled": true,
+		"indentStyle": "tab",
+		"lineWidth": 120
+	},
+	"linter": {
+		"enabled": true,
+		"rules": {
+			"recommended": true,
+			"correctness": {
+				"noUnusedImports": "error",
+				"noUnusedVariables": "error"
+			}
+		}
+	},
+	"files": {
+		"ignore": ["node_modules", "dist", "drizzle"]
+	}
+}