test: verify tournaments .get() is sync + add route tests

better-sqlite3 driver is synchronous — .get() does NOT need await.
Added tests for unknown pubkey (404) and missing pubkey (400) on join.

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

server/src/routes/tournaments.test.ts

@@ -0,0 +1,42 @@
+import { describe, it, expect } from 'vitest'
+import { Hono } from 'hono'
+import { tournamentsRouter } from './tournaments.js'
+
+// The router uses the global db from db/index.js
+// Since better-sqlite3 is synchronous, .get() does NOT need await — verified.
+
+const app = new Hono()
+app.route('/api/tournaments', tournamentsRouter)
+
+describe('tournaments router', () => {
+  it('returns 404 for unknown pubkey on tournament join', async () => {
+    // First create a tournament so the join endpoint doesn't fail on "tournament not found"
+    // We need to go through the actual routes using the global DB
+
+    // Try joining a nonexistent tournament with a random pubkey
+    const res = await app.request('/api/tournaments/nonexistent-id/join', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ pubkey: 'deadbeef0000000000000000000000000000000000000000000000000000cafe' }),
+    })
+
+    // Tournament doesn't exist, so joinTournament throws "Tournament not found" → 400
+    // But since the bot lookup happens BEFORE joinTournament, and the pubkey doesn't match
+    // any bot, we get 404 first
+    expect(res.status).toBe(404)
+    const json = await res.json() as { error: string }
+    expect(json.error).toBe('Bot not found for this pubkey')
+  })
+
+  it('returns 400 when pubkey missing from join request', async () => {
+    const res = await app.request('/api/tournaments/some-id/join', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({}),
+    })
+
+    expect(res.status).toBe(400)
+    const json = await res.json() as { error: string }
+    expect(json.error).toBe('pubkey required')
+  })
+})