[nfc]:added "(you)" indicator next to the name with reduced opacity

[17arindam]

fixes: #1320
I have implemented the requested changes by adding a "(you)" indicator next to the name with reduced opacity using withAlpha().

[alya]

Could you please update your commit message to match the commit style guidelines?

This can't possibly be an nfc if it changes a UI.

Your PR will also need to pass tests.

[gnprice]

It looks like this will need substantial revisions in order to meet our standards. In addition to all the points Alya mentioned above:

• This change will need a test of its own. See our README, which documents that requirement.
• The string "(you)", like all text aimed at the user, will need to be translated.
• … and there are smaller things we'd get to in the course of a full review.

Given that this issue is for the post-launch milestone, and that we're focusing on launch issues until the launch is ready, we won't be able to spend time coaching through those revisions in the near future, so I'll close this PR.

@17arindam if you're still interested in contributing to Zulip, I recommend you

• find an issue in the M5a or M5 milestones (see our contributor docs on picking an issue);
• and for your next PR, take a careful look through our contributor documentation and do a thorough self-review before asking others to spend time reviewing it.

[17arindam]

Thank you for your time, @gnprice I truly appreciate your feedback and will keep the mentioned points in mind for my next PR