refactor to react/vite/hono/drizzle/postgresql stack

replace vanilla TS + Bun.serve() + MariaDB with:
- frontend: React 19, Vite 6, TanStack Router/Query, Tailwind v4
- backend: Hono + @hono/node-server, Drizzle ORM, PostgreSQL, Zod
- shared: algorithm, round-state, types in src/shared/
- tooling: Biome (lint/format), Vitest (tests)
- deploy: static files at /movie-select/, API at /movie-select/api

URL scheme changes from /movies/ to /movie-select/,
API from action-based to RESTful endpoints.

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

tests/shared/algorithm.test.ts

@@ -0,0 +1,32 @@
+import { expect, test } from "vitest";
+import { decideMovie, paretoFilter } from "../../src/shared/algorithm.ts";
+
+test("paretoFilter removes dominated movies", () => {
+	const movies = ["A", "B"];
+	const people = ["P1", "P2"];
+	const ratings = { P1: { A: 1, B: 3 }, P2: { A: 2, B: 4 } };
+	expect(paretoFilter(movies, people, ratings)).toEqual(["B"]);
+});
+
+test("nash protects against hard no", () => {
+	const movies = ["Consensus", "Polarizing"];
+	const people = ["A", "B", "C"];
+	const ratings = {
+		A: { Consensus: 3, Polarizing: 5 },
+		B: { Consensus: 3, Polarizing: 5 },
+		C: { Consensus: 3, Polarizing: 0 },
+	};
+	const result = decideMovie({ movies, people, ratings });
+	expect(result.winner.movie).toBe("Consensus");
+});
+
+test("tie-breaker uses alphabetical order", () => {
+	const movies = ["Alpha", "Beta"];
+	const people = ["A", "B"];
+	const ratings = {
+		A: { Alpha: 2, Beta: 2 },
+		B: { Alpha: 2, Beta: 2 },
+	};
+	const result = decideMovie({ movies, people, ratings });
+	expect(result.winner.movie).toBe("Alpha");
+});

tests/shared/round-state.test.ts

@@ -0,0 +1,25 @@
+import { expect, test } from "vitest";
+import {
+	allUsersDone,
+	collectCompleteRatings,
+	hasCompleteRatings,
+} from "../../src/shared/round-state.ts";
+
+test("allUsersDone returns true when all done", () => {
+	expect(allUsersDone(["A", "B"], ["A", "B"])).toBe(true);
+	expect(allUsersDone(["A", "B"], ["A"])).toBe(false);
+	expect(allUsersDone([], [])).toBe(false);
+});
+
+test("hasCompleteRatings detects missing ratings", () => {
+	expect(hasCompleteRatings(["M1", "M2"], { M1: 2, M2: 5 })).toBe(true);
+	expect(hasCompleteRatings(["M1", "M2"], { M1: 2 })).toBe(false);
+});
+
+test("collectCompleteRatings filters incomplete voters", () => {
+	const result = collectCompleteRatings(["A", "B"], ["M1", "M2"], {
+		A: { M1: 1, M2: 2 },
+		B: { M1: 3 },
+	});
+	expect(result).toEqual({ A: { M1: 1, M2: 2 } });
+});