feat: Oracle packages and Github verification realm

[deelawn]

Relates to #1133

Note: the unit tests are missing from the gnorkle packages. This will not be merged without unit tests. They will be written once the design has been reviewed so no time is wasted writing and rewriting them should it be determined that structural changes need to occur.

Note 2: there are two readme files included in this PR so maybe read those first.

The PR is meant to be a first attempt at implementing a gno package that allows realms to integrate oracle functionality. There is a gh (github) application bundled in this PR that is an oracle and will be able to handle github handle -> gno address verification requests.

Everything at the gno package (/p) level falls within a v1 path because I think this package still has a lot of room for improvements.

Some things that need to be done before marking this ready for review:

• remove old first iteration code
• convert newest prototyped code from go to gno and restructure subdirectories for compatibility
• add more comments and doc strings
• create readmes
• add unit tests
• add gh verification realm tests
• make a way for the owner or an orkle instance to manage both instance and individual feeds' whitelists

Contributors' checklist...

• Added new tests, or not needed, or not feasible
• Provided an example (e.g. screenshot) to aid review or the PR is self-explanatory
• Updated the official documentation or not needed
• No breaking changes were made, or a BREAKING CHANGE: xxx message was included in the description
• Added references to related issues and PRs
• Provided any useful hints for running manual tests
• Added new benchmarks to generated graphs, if any. More info here.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 48.36%. Comparing base (dd68d61) to head (189bcfa).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1568      +/-   ##
==========================================
- Coverage   48.44%   48.36%   -0.08%     
==========================================
  Files         409      410       +1     
  Lines       61965    62783     +818     
==========================================
+ Hits        30019    30366     +347     
- Misses      29446    29881     +435     
- Partials     2500     2536      +36     

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[ajnavarro]

I have a question about this implementation: Maybe I missed something, but, how can you trust the oracle?

In other implementations, several Oracles will provide the same requested information, and the requester is in charge of comparing and checking to discard possible misleading info. Here only one Oracle is in charge of answering the request, right?

Thanks and sorry if I misunderstood something.

[deelawn]

I have a question about this implementation: Maybe I missed something, but, how can you trust the oracle?

In other implementations, several Oracles will provide the same requested information, and the requester is in charge of comparing and checking to discard possible misleading info. Here only one Oracle is in charge of answering the request, right?

Thanks and sorry if I misunderstood something.

You're completely correct; you can't trust the oracle in this first implementation unless you are also the one providing the data. The idea is to build up trust eventually using two strategies:

1. Data feeds will be able to accept task results from many agents and can aggregate the data, rewarding and penalizing them based on where their responses fall within the range of responses received.
2. There can be layers of oracles, each aggregating data from multiple agents (data sources). The results of the oracles are then themselves aggregated. A kind of oracle DAO may facilitate this.

Both strategies are just ideas and no one may want to ever try building something like that. It depends on the level of trust an oracle has with the data providers contributing to its feeds. But if someone would like to do that, I think the structure is defined in this package to allow it to happen.

The first big win with this PR is to provide the tools to enable realms to bring offchain data onchain so it can be used in their applications.

[moul]

LGTM

[deelawn]

thanks Manfred. I will add some unit tests before merging.