refactor: convert to bun workspaces monorepo

- Move web app into apps/web/
- Create packages/shared/ with shared types
- Create plugins/decky-vault/ scaffold
- Root package.json manages workspaces only

apps/web/lib/auth/__tests__/auth.test.ts

@@ -0,0 +1,43 @@
+import { describe, it, expect, beforeAll } from "vitest"
+
+// Auth integration tests require a fully-functional PostgreSQL database with
+// the application schema (set via DATABASE_URL). If the env var is missing or
+// the DB is unreachable, every test is skipped rather than failing.
+let dbUsable = false
+let dbHelper: any
+
+if (process.env.DATABASE_URL) {
+  try {
+    const { db } = await import("@/lib/db/index")
+    await db.execute("SELECT 1")
+    dbUsable = true
+  } catch {
+    dbUsable = false
+  }
+}
+
+describe(dbUsable ? "Better-Auth integration" : "Better-Auth integration (skipped: database not usable)", () => {
+  beforeAll(async () => {
+    if (!dbUsable) return
+    const { getTestHelpers } = await import("@/lib/auth/test")
+    dbHelper = await getTestHelpers()
+  })
+
+  it("should create a user", async () => {
+    if (!dbUsable || !dbHelper) return
+    const user = await dbHelper.createUser({ email: "test@example.com" })
+    expect(user.email).toBe("test@example.com")
+  })
+
+  it("should create a session for a user", async () => {
+    if (!dbUsable || !dbHelper) return
+    const user = await dbHelper.createUser({ email: "session-test@example.com" })
+    await dbHelper.saveUser(user)
+
+    const { session, headers } = await dbHelper.login({ userId: user.id })
+    expect(session.userId).toBe(user.id)
+    expect(headers.get("cookie")).toBeTruthy()
+
+    await dbHelper.deleteUser(user.id)
+  })
+})