Add server, routes, views, CLI, CSS, and integration tests

- Server factory with Fastify plugins (JWT, cookie, multipart, formbody, static)
- Auth middleware: requireAuth preHandler (401 for API, redirect for pages)
- Auth API routes: POST /api/v1/auth/login, POST /api/v1/auth/logout
- File API routes: GET/POST /api/v1/files, DELETE /api/v1/files/:id
- Page routes: /, /login, /logout, /upload, /files, /files/:id/delete, /f/:id, /f/:id/raw
- HTML views: layout, login, upload, file-list, file-view, not-found
- CLI register-user script
- public/style.css dark theme
- Test helpers: createTestApp, loginAs, buildMultipart
- Integration tests for auth API, file API, and page routes (51 tests passing)
- Update CLAUDE.md with red/green TDD and commit instructions

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

src/cli/register-user.ts

@@ -0,0 +1,33 @@
+import { parseArgs } from 'util';
+import { loadConfig } from '../config.ts';
+import { initDb } from '../db/schema.ts';
+import { createUser, getUserByUsername } from '../db/users.ts';
+import { hashPassword } from '../services/auth.ts';
+
+const { values } = parseArgs({
+  args: process.argv.slice(2),
+  options: {
+    username: { type: 'string' },
+    password: { type: 'string' },
+  },
+});
+
+const { username, password } = values;
+
+if (!username || !password) {
+  console.error('Usage: npm run register-user -- --username <user> --password <pass>');
+  process.exit(1);
+}
+
+const config = loadConfig();
+const db = initDb(config.dbPath);
+
+const existing = getUserByUsername(db, username);
+if (existing) {
+  console.error(`User "${username}" already exists.`);
+  process.exit(1);
+}
+
+const passwordHash = await hashPassword(password);
+createUser(db, { username, passwordHash });
+console.log(`User "${username}" created successfully.`);