Add OpenSourceObserver stats to explorer

[MasterHW]

Fixes: Feature add - show codebase-derived insights to Explorer project page above Karma GAP section. Data provided by Open Source Observer.

Description

Created relevant OSO files in a manner similar to the existing Karma GAP implementation. Should fetch information relevant to project age, number of code contributors, and "velocity" (increasing activity or not) and show them in the UI. If no information can be fetched, show nothing.

Checklist

This PR:

• Does it add new payout or donation token? In this case, have they been added to the indexer to avoid it to crash?
• Includes only changes relevant to the original ticket. Significant refactoring needs to be separated.
• Doesn't disable eslint rules.
• Doesn't work around the type checker (including but not limited to: type casts, non-null assertions, @ts-ignore, unjustified optional values).
• Doesn't contain commented out code.
• If adding/updating a feature, it adds/updates its test script on Notion.

[vercel]

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Name	Status	Preview	Comments	Updated (UTC)
builder	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Apr 30, 2024 10:27pm
builder-staging	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Apr 30, 2024 10:27pm
explorer	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Apr 30, 2024 10:27pm
explorer-staging	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Apr 30, 2024 10:27pm
manager	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Apr 30, 2024 10:27pm
manager-staging	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Apr 30, 2024 10:27pm

[sentry-io]

🔍 Existing Issues For Review

Your pull request is modifying functions with the following pre-existing issues:

📄 File: packages/grant-explorer/src/features/round/ViewProjectDetails.tsx

Function	Unhandled Issue
ViewProjectDetails	TypeError: Cannot read properties of null (reading 'metadata') mapApplicationToProject(features/projects/hooks/u... Event Count: 6 Affected Users: 7

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[MasterHW]

Failing because Error: OpenSourceObserver API key not set., which is expected behaviour if no REACT_APP_OSO_API_KEY. Where can I set this for the job?

[ryscheng]

This is so cool!!
Thank you for putting this together!

I just wanted to give you a heads up that we're trying to get to v1 of our marts models:
That means you should start to see _v1, _v2 style major versioning in the next set of data pipeline runs. We're also improving our style guide for model naming so folks know what to expect in the future. Thanks for being patient with us as we steady these models. We'll aim to use this versioning to avoid major breakages in the future.

But for this iteration, we apologize if this breaks any of your integrations. Please see our GraphQL explorer to see the current status of the model names
https://cloud.hasura.io/public/graphiql?endpoint=https://opensource-observer.hasura.app/v1/grap