feat/message-reactions

[DimaIvashchuk]

I have added a minimal working functionality for message reactions.
@kesha-antonov there might be a mess, sorry for that:) but I hope you will get basic understanding.
There are couple of things to consider:

1. Full modal with emojies comes from my personal npm lib that I have created for my self, it is not really well tested and there are couple of things that can be improved.
2. In the original implementation I use bottom sheet from gorham. here is not. You might consider using it
3. also the animations might be uncompleted or inappropriate.
4. Also i didn't add an ability to fast react on double tap, but it should be pretty much straightforward

[kesha-antonov]

Thanks @DimaIvashchuk! I rebased this onto current master and did a cleanup pass so it can land:

• Rebased & conflicts resolved against the latest master (the animated day header work had since touched Bubble).
• Dropped the unrelated reformatting so the diff is reactions-only (now ~1.3k insertions vs the original ~2k/600).
• No new core dependencies. The full emoji browser (react-native-emoji-chooser + react-native-svg + async-storage) moved entirely into the example, wired via the renderReactionPicker override. The library itself only uses react-native-gesture-handler and react-native-reanimated, which are already peer deps. Core ships a lightweight quick picker; consumers opt into a full browser if they want one.
• Added a README section (usage, props, screenshots) and an example screen.
• Verified on an Android emulator: quick picker, reaction pills (with counts + active state), and the full emoji browser all render correctly with no native crash.

Your original commit is preserved as the feature commit (authored by you); the docs are a follow-up commit. Merging once CI is green.