fix: inpainting OOM & pipeline error handling

refactor(core): rewrite data model as Scene + Op + content-addressed blobs

Adds the ability to reorder pages (#393)

feat: google fonts

perf: improve ctd

feat: blob API, bubble/AOT-inpainting models, and rendering redesign

refactor(ui): centralize error handling with XState

refactor: simplify Tauri setup and dev server

refactor: rewrite backend storage, config, and runtime

refactor: OpenAPI codegen with utoipa and Orval

refactor: merge crates

refactor: split modules

feat: download progress indicator

chore: reorganize code

feat: google fonts

refactor: re-introduce koharu-core

refactor: use koharu-ml

feat: text rendering via Rust

perf: download with http range

feat: add tracing events for download events

feat: Implement core application structure and functionality