* Add Labs screen:
- Make `Feature` have an `isInLabs` boolean to distinguish private feature flags from public ones.
- Have `FeatureFlagsService` provide the list of available flags.
- Display the labs item in the settings screen only if there are available public features.
- Remove public feature toggles from developer options.
- Implement the labs screen with the public features.
- Add a clear cache step to the threads feature toggle
- Update screenshots
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Co-authored-by: ElementBot <android@element.io>
2 replace all actions have been performed:
- "SPDX-License-Identifier: AGPL-3.0-only" to "SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial"
- "Please see LICENSE in the repository root for full details." to "Please see LICENSE files in the repository root for full details."
- Removed `StaticFeatureFlagProvider`.
- Always provide `PreferencesFeatureFlagProvider`.
- For the default values of feature flags, use a lambda with a `BuildMeta` parameter so we can customize the return value based on its data.
