Use the setupVars.conf option TEMPERATUREUNIT, plus slight rearrangement of settings page

[rdwebdesign]

What does this PR aim to accomplish?

Allow the selection of temperature unit shown on the web interface via setupVars.conf, like other interfaces (PADD/chronometer) already do.

Currently the web interface always defaults to "C" (Celcius). The user must manually select the unit on Setting page for every device/browser used.

Note:
The suggest code here will use a global unit and remove the ability to use different units on each device (which was probably never the desired behavior).

How does this PR accomplish the above?

Changing the code to use a new behavior:

• if the option TEMPERATUREUNIT is set in setupVars.conf file, the value will be used.
• if there is no unit set in setupVars.conf, but the browser has an old value set on locastorage, the localstorage value will be used and stored in setupVars.conf file.
• if there is no unit set in setupVars.conf or localstorage, "C" will be used as default value.

Also:

• The temperature unit will be set GLOBALLY and not per browser.
• changing the value on the web interface WILL CHANGE setupVars.conf.

Link documentation PRs if any are needed to support this PR:

The TEMPERATUREUNIT description on docker-pi-hole repository will need to be updated to reflect the new behavior

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[PromoFaux]

App appears to work, though regarding this part:

The temperature unit will be set GLOBALLY and not per browser.

With that in mind, we should probably move this out of the Per-browser settings box, and into the Web interface settings box?

[rdwebdesign]

With that in mind, we should probably move this out of the Per-browser settings box, and into the Web interface settings box?

I agree.

[PromoFaux]

I think it looks fine, however it now introduces something else... Changing the temperature unit is automatically updated when switching between them without having to press save...

The other options in that same dialog require the usage of the save button. Two suggestions:

• Make the others change on selection rather than pressing save
• Separate the temperature unit selection out to another box / separate part of the same box to show that Save is not needed for this item

[rdwebdesign]

Yeah... I notice this behavior.

What do you think about this?

[PromoFaux]

Yep - that looks good to me

[pralor-bot]

This pull request has been mentioned on Pi-hole Userspace. There might be relevant details there:

https://discourse.pi-hole.net/t/pi-hole-ftl-v5-21-web-v5-18-4-and-core-v5-15-4-released/61096/1