feat: update thread messages in the background based on WS events

[MartinCupela]

Motivation Every time the Thread component is rendered a new HTTP request is fired to retrieve its data. This happens even though the client could update the thread state based on incoming WS events:

New thread reply event (`message.new` with the `parent_id` attr)

{
    "type": "message.new",
    "cid": "messaging:brazil",
    "channel_id": "brazil",
    "channel_type": "messaging",
    "message": {
        "id": "SmithAnne-RagV8FZgHpmPMb2ES8wda",
        "text": "b",
        "html": "<p>b</p>\n",
        "type": "reply",
        "user": {
            "id": "SmithAnne",
            "role": "user",
            "created_at": "2022-01-27T08:28:28.412254Z",
            "updated_at": "2022-05-05T19:19:25.913957Z",
            "last_active": "2022-06-09T09:14:23.653692038Z",
            "banned": false,
            "online": true,
            "image": "https://cdn.fakercloud.com/avatars/miguelkooreman_128.jpg",
            "nickname": "Ann",
            "name": "SmithAnne"
        },
        "attachments": [],
        "latest_reactions": [],
        "own_reactions": [],
        "reaction_counts": {},
        "reaction_scores": {},
        "parent_id": "SmithAnne-Vmzj4d94czPfMdSg4aeXN",
        "reply_count": 0,
        "cid": "messaging:brazil",
        "created_at": "2022-06-09T09:22:19.552958Z",
        "updated_at": "2022-06-09T09:22:19.552958Z",
        "shadowed": false,
        "mentioned_users": [],
        "silent": false,
        "pinned": false,
        "pinned_at": null,
        "pinned_by": null,
        "pin_expires": null
    },
    "user": {
        "id": "SmithAnne",
        "role": "user",
        "created_at": "2022-01-27T08:28:28.412254Z",
        "updated_at": "2022-05-05T19:19:25.913957Z",
        "last_active": "2022-06-09T09:14:23.653692038Z",
        "banned": false,
        "online": true,
        "nickname": "Ann",
        "name": "SmithAnne",
        "image": "https://cdn.fakercloud.com/avatars/miguelkooreman_128.jpg"
    },
    "watcher_count": 1,
    "created_at": "2022-06-09T09:22:19.567940859Z"
}

Parent message update event

{
    "type": "message.updated",
    "cid": "messaging:brazil",
    "channel_id": "brazil",
    "channel_type": "messaging",
    "message": {
        "id": "SmithAnne-Vmzj4d94czPfMdSg4aeXN",
        "text": "",
        "html": "",
        "type": "regular",
        "user": {
            "id": "SmithAnne",
            "role": "user",
            "created_at": "2022-01-27T08:28:28.412254Z",
            "updated_at": "2022-05-05T19:19:25.913957Z",
            "last_active": "2022-06-09T09:14:23.653692038Z",
            "banned": false,
            "online": true,
            "nickname": "Ann",
            "name": "SmithAnne",
            "image": "https://cdn.fakercloud.com/avatars/miguelkooreman_128.jpg"
        },
        "attachments": [
            {
                "type": "audio",
                "title": "Audio Clip (2022-03-21_10-23-53-413).m4a",
                "asset_url": "https://us-east.stream-io-cdn.com/1145265/attachments/e1d6a888-f6b9-4a5a-b3f0-ac99049712fb.Audio%20Clip%20%282022-03-21_10-23-53-413%29.m4a?Key-Pair-Id=APKAIHG36VEWPDULE23Q&Policy=eyJTdGF0ZW1lbnQiOlt7IlJlc291cmNlIjoiaHR0cHM6Ly91cy1lYXN0LnN0cmVhbS1pby1jZG4uY29tLzExNDUyNjUvYXR0YWNobWVudHMvZTFkNmE4ODgtZjZiOS00YTVhLWIzZjAtYWM5OTA0OTcxMmZiLkF1ZGlvJTIwQ2xpcCUyMCUyODIwMjItMDMtMjFfMTAtMjMtNTMtNDEzJTI5Lm00YSoiLCJDb25kaXRpb24iOnsiRGF0ZUxlc3NUaGFuIjp7IkFXUzpFcG9jaFRpbWUiOjE2NTU5NzM0NjJ9fX1dfQ__&Signature=k~QKGZLR~z6zC~1-F~NPPOaYOcbWbyK4tqhozWAMujDYdwe1D2IfVXhLoqGlz9TmvGTVek96TrNAdr70LbqDBn7LRByRYZIkOW7iNvqmi0kTjmboEaiMhhd8muFy2vlPImZLNv7ecv-56~Xj0HW5NzCC3qFHUu-k-XquUxKUxife1CJgT2JvuljaOzt0BcMoUJGoM8DAYsavq9wx~ZF1xXNzVFsmLR6-eFgAV4pqIk85dWpS-aak~E4Mcvtv5rM7IqfQ0G-ty2oAqFqx14-E6u4YZUgpQw9BrMKudzS9BBbV-r6Vk2rRMK-cUV6Wg6eNtaVmuUk6cHZJee4osrfqzA__",
                "file_size": 36132,
                "mime_type": "audio/x-m4a"
            }
        ],
        "latest_reactions": [],
        "own_reactions": [],
        "reaction_counts": {},
        "reaction_scores": {},
        "reply_count": 2,
        "thread_participants": [
            {
                "id": "SmithAnne",
                "role": "user",
                "created_at": "2022-01-27T08:28:28.412254Z",
                "updated_at": "2022-05-05T19:19:25.913957Z",
                "last_active": "2022-06-09T09:14:23.653692038Z",
                "banned": false,
                "online": true,
                "nickname": "Ann",
                "name": "SmithAnne",
                "image": "https://cdn.fakercloud.com/avatars/miguelkooreman_128.jpg"
            }
        ],
        "cid": "messaging:brazil",
        "created_at": "2022-06-09T08:37:42.844888Z",
        "updated_at": "2022-06-09T08:37:42.844888Z",
        "shadowed": false,
        "mentioned_users": [],
        "silent": false,
        "pinned": false,
        "pinned_at": null,
        "pinned_by": null,
        "pin_expires": null
    },
    "user": {
        "id": "SmithAnne",
        "role": "user",
        "created_at": "2022-01-27T08:28:28.412254Z",
        "updated_at": "2022-05-05T19:19:25.913957Z",
        "last_active": "2022-06-09T09:14:23.653692038Z",
        "banned": false,
        "online": true,
        "name": "SmithAnne",
        "image": "https://cdn.fakercloud.com/avatars/miguelkooreman_128.jpg",
        "nickname": "Ann"
    },
    "created_at": "2022-06-09T09:22:19.567937971Z"
}

That way the loading UI could be shown only the first time the Thread component is open. Since then the client holds its reference in a mapping, which can be updated in the background as the WS events come in.

Acceptance Criteria

1. Fire the /replies HTTP query only on the first opening of the existing thread (message loaded with reply_count > 0)
2. Display the UI loading indicator only when hitting the replies endpoint