Add timestamps extension

[kaiguang]

Description

Screencast

Checklist

• [x] I read the extension guidelines
• [x] I read the documentation about publishing
• [x] I ran npm run build and tested this distribution build in Raycast
• [x] I checked that files in the assets folder are used by the extension itself
• [x] I checked that assets used by the README are placed outside of the metadata folder

[raycastbot]

Congratulations on your new Raycast extension! :rocket:

We will aim to make the initial review within five working days. Once the PR is approved and merged, the extension will be available on our Store.

[kaiguang]

Hi @pernielsentikaer, thanks for showing me the built-in timestamp features. Unfortunately there are some subtle differences between the extension in this PR and the built-in timestamp helpers:

1. I want the timestamps to be in milliseconds, the built-in is only in seconds.
2. I want the extension to insert the current timestamp directly to where the cursor is, the built-in only copies it to the clipboard
3. When converting a timestamp to date, I want to see the timezone in my locale, something like Thu Apr 11 2024 10:27:07 GMT-0600 (Mountain Daylight Saving Time), not the hard to read format like February 23, 56248 at 05:05:42 GMT-07:00 from the built-in
4. When converting a timestamp to date, I want to insert the date directly to the cursor location, the built-in only copies it to the clipboard
5. The built-in doesn't offer me to insert today's date in the format like 2024-04-11 Thu

[pernielsentikaer]

There is already a lot of extensions doing date formatting in the store, maybe it would be better to enhance one of them if the feature is not already present - most of the things can be done with snippets too

1. You can setup a snippet with this content {date format="A"} - that should give you time in milliseconds
2. With the snippet it's possible to expand with a keyword like !ms
3. A snippet with {date format="yyyy-MM-dd E"} should give you this output