chore: initial project scaffold

Set up Mangalord with a Rust/axum backend, SvelteKit frontend, Postgres,
and Docker Compose deployment. Establishes the architecture and TDD
patterns the project will extend:

- Hexagonal-ish backend layering (domain / repo / storage / api) with
  a pluggable Storage trait (LocalStorage today, S3 as a future impl).
- Initial migration: users, mangas, chapters, bookmarks.
- Vertical slice for mangas (list, search, create, get) with
  #[sqlx::test] integration coverage and storage unit tests.
- SvelteKit frontend using Svelte 5 runes, typed API client, Vitest
  unit tests and Playwright e2e with route mocking.
- CLAUDE.md documenting layering, TDD/git/SemVer workflow rules, and
  extension points (tags, fulltext search, OCR, S3, auth).
- Project-scoped .claude/settings.json with permission allowlist for
  the toolchain (git, cargo, npm/vite, docker, psql, gh, doc fetches).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/src/lib/api/client.ts

@@ -0,0 +1,33 @@
+// All backend calls go through this module. Components and routes import
+// the typed helpers below — they do not call fetch directly.
+
+const BASE = (typeof import.meta !== 'undefined' && import.meta.env?.VITE_API_BASE) || '/api';
+
+export class ApiError extends Error {
+    constructor(
+        public readonly status: number,
+        message: string
+    ) {
+        super(message);
+        this.name = 'ApiError';
+    }
+}
+
+export async function request<T>(path: string, init?: RequestInit): Promise<T> {
+    const res = await fetch(`${BASE}${path}`, init);
+    if (!res.ok) {
+        const text = await res.text().catch(() => '');
+        throw new ApiError(res.status, text || `${res.status} ${res.statusText}`);
+    }
+    return (await res.json()) as T;
+}
+
+export type Manga = {
+    id: string;
+    title: string;
+    author: string | null;
+    description: string | null;
+    cover_image_path: string | null;
+    created_at: string;
+    updated_at: string;
+};