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>

backend/src/repo/manga.rs

@@ -0,0 +1,76 @@
+//! Manga persistence.
+//!
+//! Plain async functions over `&PgPool` rather than a repository struct —
+//! each function is easy to test in isolation with `#[sqlx::test]`, and
+//! handlers depend only on `sqlx::PgPool`, not on a trait object. Swap to
+//! a trait + impl if a second backend ever becomes necessary.
+
+use sqlx::PgPool;
+use uuid::Uuid;
+
+use crate::domain::manga::{Manga, NewManga};
+use crate::error::{AppError, AppResult};
+
+#[derive(Debug, Clone)]
+pub struct ListQuery {
+    pub search: Option<String>,
+    pub limit: i64,
+    pub offset: i64,
+}
+
+impl Default for ListQuery {
+    fn default() -> Self {
+        Self { search: None, limit: 50, offset: 0 }
+    }
+}
+
+pub async fn list(pool: &PgPool, query: &ListQuery) -> AppResult<Vec<Manga>> {
+    let pattern = query.search.as_deref().map(|s| format!("%{}%", s));
+    let rows = sqlx::query_as::<_, Manga>(
+        r#"
+        SELECT id, title, author, description, cover_image_path, created_at, updated_at
+        FROM mangas
+        WHERE $1::text IS NULL
+           OR title ILIKE $1
+           OR COALESCE(author, '') ILIKE $1
+        ORDER BY created_at DESC
+        LIMIT $2 OFFSET $3
+        "#,
+    )
+    .bind(pattern)
+    .bind(query.limit)
+    .bind(query.offset)
+    .fetch_all(pool)
+    .await?;
+    Ok(rows)
+}
+
+pub async fn get(pool: &PgPool, id: Uuid) -> AppResult<Manga> {
+    sqlx::query_as::<_, Manga>(
+        r#"
+        SELECT id, title, author, description, cover_image_path, created_at, updated_at
+        FROM mangas
+        WHERE id = $1
+        "#,
+    )
+    .bind(id)
+    .fetch_optional(pool)
+    .await?
+    .ok_or(AppError::NotFound)
+}
+
+pub async fn create(pool: &PgPool, input: NewManga) -> AppResult<Manga> {
+    let row = sqlx::query_as::<_, Manga>(
+        r#"
+        INSERT INTO mangas (title, author, description)
+        VALUES ($1, $2, $3)
+        RETURNING id, title, author, description, cover_image_path, created_at, updated_at
+        "#,
+    )
+    .bind(&input.title)
+    .bind(&input.author)
+    .bind(&input.description)
+    .fetch_one(pool)
+    .await?;
+    Ok(row)
+}

backend/src/repo/mod.rs

@@ -0,0 +1 @@
+pub mod manga;