* add axum sse example
* fix: make the sse axum folder name correct
* feat: add common modules for Axum SSE example
This commit adds supporting modules for the Axum Server-Sent Events (SSE) example:
- Added `counter.rs` with a simple counter router implementation
- Added `jsonrpc_frame_codec.rs` for decoding JSON-RPC frames
- Created a `mod.rs` to expose these modules
- Removed the previous SSE example configuration from Cargo.toml
* refactor: remove main.rs and update Cargo.toml for WASM compatibility
This commit makes two key changes:
1. Removes the main.rs file and make it a example
2. Add a wasi_std_io example
* refactor: simplify WASI I/O handling in example and fmt
Merged AsyncInputStream and AsyncOutputStream into a single WasiFd struct with std_in() and std_out() methods, reducing code duplication and improving clarity of the WASI standard I/O example.
* move examples to root
