migrate: replace NextAuth.js with Better Auth

- Install better-auth and @better-auth/drizzle-adapter
- Create src/lib/auth.ts with Better Auth configuration using bcrypt
- Update database schema: change auth table IDs from uuid to text
- Update route handler from /api/auth/[...nextauth] to /api/auth/[...all]
- Update tRPC context and middleware for Better Auth session handling
- Update client components to use Better Auth APIs (signIn, signOut)
- Update seed script with text-based IDs and correct account schema
- Fix type errors in wizard components (robotId, optional chaining)
- Fix API paths: api.robots.initialize -> api.robots.plugins.initialize
- Update auth router to use text IDs for Better Auth compatibility

Note: Auth tables were reset - users will need to re-register.

src/lib/auth.ts

@@ -0,0 +1,79 @@
+import { betterAuth } from "better-auth";
+import { drizzleAdapter } from "@better-auth/drizzle-adapter";
+import { nextCookies } from "better-auth/next-js";
+import { db } from "~/server/db";
+import {
+  users,
+  accounts,
+  sessions,
+  verificationTokens,
+} from "~/server/db/schema";
+import bcrypt from "bcryptjs";
+
+const baseURL =
+  process.env.NEXTAUTH_URL ||
+  process.env.BETTER_AUTH_URL ||
+  "http://localhost:3000";
+
+export const auth = betterAuth({
+  baseURL,
+  database: drizzleAdapter(db, {
+    provider: "pg",
+    schema: {
+      user: users,
+      account: accounts,
+      session: sessions,
+      verification: verificationTokens,
+    },
+  }),
+  emailAndPassword: {
+    enabled: true,
+    password: {
+      hash: async (password: string) => {
+        return bcrypt.hash(password, 12);
+      },
+      verify: async ({
+        hash,
+        password,
+      }: {
+        hash: string;
+        password: string;
+      }) => {
+        return bcrypt.compare(password, hash);
+      },
+    },
+  },
+  session: {
+    expiresIn: 60 * 60 * 24 * 30,
+    updateAge: 60 * 60 * 24,
+    modelName: "session",
+    fields: {
+      id: "id",
+      token: "token",
+      userId: "userId",
+      expiresAt: "expiresAt",
+      ipAddress: "ipAddress",
+      userAgent: "userAgent",
+    },
+  },
+  account: {
+    modelName: "account",
+    fields: {
+      id: "id",
+      providerId: "providerId",
+      accountId: "accountId",
+      userId: "userId",
+      accessToken: "accessToken",
+      refreshToken: "refreshToken",
+      expiresAt: "expiresAt",
+      scope: "scope",
+    },
+  },
+  pages: {
+    signIn: "/auth/signin",
+    error: "/auth/error",
+  },
+  plugins: [nextCookies()],
+});
+
+export type Session = typeof auth.$Infer.Session;