[feat: invoke] initial invoke implementation

[zhongkechen]

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Issue Link, if available

#18

Description

Implement the chained invocation feature

Demo/Screenshots

Deployed to Lambda and the happy case succeeded

Checklist

• I have filled out every section of the PR template
• I have thoroughly tested this change

Testing

Unit Tests

Have unit tests been written for these changes? Yes

Integration Tests

Have integration tests been written for these changes? Yes

Examples

Has a new example been added for the change? (if applicable) Yes

[phipag]

Only some minor nits picks / comments. Looks like a great start.

One note regarding the formatting. We setup Spotless for formatting. Before pushing you can run:

mvn spotless:apply

which will apply the common formatting we have (and also add license headers automatically).

You can automate this with a git commit hook which can be setup using:

mvn spotless:install-git-pre-push-hook 

[maschnetwork]

Some minor comments on naming and switch case for .get

[zhongkechen]

We setup Spotless for formatting

@phipag That's great! I didn't know Spoltless is used. Is there an IntelliJ plugin for it?

[phipag]

We setup Spotless for formatting

@phipag That's great! I didn't know Spoltless is used. Is there an IntelliJ plugin for it?

There is this plugin: https://plugins.jetbrains.com/plugin/22455-spotless-applier. Note that some plugins only work with Gradle but not Maven.

We chose it mainly because it is IDE independent + has a CLI that can be used in a GitHub action to lint code style and also license headers.

[maschnetwork]

See comments. Please also add end user docs to README.

[zhongkechen]

Ran the cloud-based integration tests again and succeeded

[zhongkechen]

See comments. Please also add end user docs to README.

Add a commit to update README, although I think we need to move the SDK tutorial to a separate doc

[maschnetwork]

LGTM