Add translation key for time ago

[CommanderStorm]

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Description

Add translation keys

Originally, this was raised in #4400 but said PR had a bad rebase.
Doing this one cleanly is simpler

Type of change

Please delete any options that are not relevant.

• Other

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings

Screenshots (if any)

[CommanderStorm]

The main reason the heartbeat time indication was not translated, is because "the minimum width of heartbeats where the time indication should be displayed" is a fixed value. If the text can be translated, this width becomes variable. I don't see an easy way of handling this.

Although I suppose we could just increase the value to be much larger than necessary to be safe.

This is the closest i can push the values and the longest that they can be (after that, they merge into one long string):

=> I don't think this will actually be an issue or am I missing something @chakflying

[CommanderStorm]

Given that this is just a translation, I am going to skip a review for this one.
A self-review is likely fine for this ^^

[CommanderStorm]

fixed formatting