Feature flags UI improvements

[liyiy]

• [ ] Make enable flag button more prominent on the feature flag screen and without having to go into edit mode
• [x] Multivariate code snippet instructions
• [ ] Add more useful automatic metrics/insights on the flag
• [ ] Deleting a feature flag success toast is buggy. Also, add a double confirmation when deleting enabled flags.
• [ ] Rollouts with multiple groups should at least partially show which groups they belong to on the feature flags table
• [ ] With the addition of tags, the feature flags table is also now too long width wise
• [ ] Add "experiment" tags by default to experiment feature flags
  • https://github.com/PostHog/posthog/pull/13879 (can be picked up)

[annikaschmid]

QA of code snippet

General

• [x] React is missing from the list of libraries, and we should add Flutter once we have the docs

Design

• [ ] Position of Auto rollback in read view

In the feature flags view (read/non edit), the Auto rollback is in between the release conditions and "how to implement". Did we do this on purpose? It looks a bit weird because the Auto rollback doesn't have any content. We might not need to fix this now since it's not available, but we shouldn't forget about it

• [x] Hierarchy of code example headlines

If we think of the structure of the page, this is how I see it ... X. Served Value Y. Release Conditions Z. How to implement Z.1 Payloads Z.2 Bootstrapping

The visual hierarchy currently doesn't reflect that. Z and Z.1/Z.2 are bigger than X and Y. Can we update this to match the hierarchy? If we don't have a headline smaller than what we have for "Release Conditions" at the moment, I would fall back and use it for both Z and Z.1/Z.2

• [x] Center "Advanced settings"

On hover and when selected, the content is currently misaligned/not centered

• [ ] Remove box around "Permissions" and change headline styling to make it the same as "Auto rollback"

Wording

• [x] ReactNative -> React Native

• [x] Bootstrap / Bootstrapping For the checkboxes, we say "Show Bootstrap option" When I select it, the headline then says "Bootstrapping". I think this should be the same and call the checkbox "Show Bootstrapping option". Same for payloads, where we currently say "Payload" / "Payloads"

• [x] Go vs Golang We call it 'Go' in our docs, but 'Golang' in the UI. This is super minor, but still would be nice to be aligned

Side note: I love that "Check the docs" goes to the selected SDK. Nicely done :)