[Feature request] add clickable support for conventional tags

[awmottaz]

Is your feature request related to a problem? Please describe.

Related to #96

Describe the solution you'd like

Add support for some conventional tag names, such as

• tag
• link
• mailto

Then, if I have the following task:

send feedback for the report tag:email mailto:[email protected] link:https://thereport.net

I could...

• Click on "email" to filter tasks that have tag:email
• Click on "[email protected]" to open an email composition window (like mailto links on the web)
• Click on "https://thereport.net" to open the link in my browser

Describe alternatives you've considered

I need to do manual searching to filter by the tag, and I need to open the task for editing to copy/paste the email or link.

Additional context

None

[JMoerman]

7252b2a implements handling URIs that look like: <scheme>://<something> or have mailto, tel or sms as URI scheme. link:https://thereport.net won't work, but https://thereport.net can now be clicked on.

I'm not convinced that adding tag is a good idea as using @email instead of tag:email can already be used to filter tasks in this way.