Migrated env feature flags to openfeature

[kurtisassad]

Link to Issue

Closes: #6701

Description of Changes

• Migrates old feature flag system to use openfeature.

Test Plan

With the .env:

FLAG_COMMUNITY_STAKE=true
FLAG_NEW_ADMIN_ONBOARDING=true

• Check community stakes by creating a staked community with the sepolia chain node.
• Create community and check that the new admin onboarding section appears

[jnaviask]

@kurtisassad deployment plan? What new infra does this involve? How is it managed?

[kurtisassad]

@jnaviask This particular PR has no required deployment plan. The overall deployment plan will be:

1. Merge this PR (This converts our .env usage to use the openfeature interface)
2. Merge this PR and follow it's required deployment Added unleash provider for openconfig #6707 (This adds unleash as the implementation for production)

The reason for this is that some developers have expressed that they would like to continue using the old .env feature flag for local development instead of being forced to connect to our unleash server.

[Rotorsoft]

Looks good to me, but would prefer if @masvelio reviews and approves UI changes.

[masvelio]

we have this warning in the console now, which might lead to not expected behaviours in the future. Related to this

Apart from it, it looks good and seems to work fine as well. So to understand it correctly. My local .env will always override the flag value from the unleash?

[kurtisassad]

My local .env will always override the flag value from the unleash?

Correct

[Rotorsoft]

LGTM 🚀