feat: integrate flutter_rust_bridge

[LucasXu0]

Prerequisites

1. Install the code generator: cargo install flutter_rust_bridge_codegen
2. Ensure you have Rust version 1.85 or higher installed
3. Generate the bridge code with: flutter_rust_bridge_codegen generate

Troubleshooting

Compilation Error with Rust <1.85
If you encounter this error:

Copy
Compiling rust_lib_appflowy v0.1.0
error[E0658]: `#[unsafe()]` markers for attributes are experimental
   --> src/frb_generated.rs:249:5
    |
249 |     flutter_rust_bridge::frb_generated_boilerplate_io!();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Solution: Update your Rust installation to version 1.85 or higher using:

rustup update stable