[Improvement] Update display of tags in counters

[tprudentova]

2.6.5, all environments

Current behaviour:

1. When the chat is unmuted:

• If there's only one unread message and it's a tag, a "@" + counter is displayed, all blue
• If there's more than 1 unread message including a message with a tag: just a blue counter

2. When the chat is muted:

• If there's only one unread message and it's a tag, a "@" + counter is displayed, all blue
• If there's more than 1 unread message including a message with a tag: a blue counter of messages with a tag (not all unread messages)

Video of current behaviour:

https://github.com/user-attachments/assets/ed436a28-4c7e-4090-9aad-d56cb8c23ab6

Expected behaviour

1. When the chat is unmuted:

User sees a blue "@" and a blue counter of ALL unread messages

2. When the chat is muted:

User sees a grey "@" and a grey counter of ALL unread messages