Finish porting core features from "agent-js"

[neeboo]

** updates**

1. Candid UI is not needed
2. Candid parser should be separate package as a builder

TODO:
[x] auth-client, used for authenticate a flutter app from Internet Identity authing app. tracking this issue: Changes will be required for Internet Identity, adapt to use a web pop window to receive callback
[x] wallet, keysmith, rosetta-api packages implemented

[] candid-ui/candid core, used for generating default ui like the web version
[] candid-parser, used for automated generating Candid file to dart code. Either we use candid-rs build script or use source_gen of flutter tool chain.