Tweak settings level and add changed-only toggle

[DL6ER]

What does this implement/fix?

Remove settings level selection in favor of a simple settings level toogle in the same place:

Furthermore, we add a feature requested on Discourse: A toggle in the empty place on the All settings page that allows you to hide all default-valued config options:

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Related issue or feature (if applicable): N/A

Pull request in docs with documentation (if applicable): N/A

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[DL6ER]

Changed the color in the last commit to match the icon color:

[yubiuser]

[yubiuser]

Switching to "All settings" sets the level to basic and no items are shown.

[yubiuser]

Suggesting

settings.js L44 to change title="This is an advanced level setting to title="This is an expert level setting

[rdwebdesign]

title="This is an expert level setting"

Maybe we should remove the "This is" part and use only title="Expert level setting".

[DL6ER]

When users decide to manually browse to https://pi.hole/admin/settings/all they will see:

[rdwebdesign]

Sending users to a different page and then back doesn't seem like the best solution. It's a bit of a bad user experience.

Suggestions - If this page is accessed using basic level:

1. show the level toggle or
2. do not allow and redirect to /settings/system or /index
3. automatically set Expert level (this is not an access level intended to block users without permissions, it is just a way to simplify the settings pages (view level). The user can already change the level whenever they wish).

[DL6ER]

You have to consider that nobody may ever see this. It's the edge case of the edge case

To me no. 2 sounds best, least obscure behavior in contrast to magically changing boxes or silent settings changes

Bug fixed

[yubiuser]

Some items lost/miss the "expert level" icon:

DNS/Conditional forwarding
Web/Exclusions
Web/Active sessions
Privacy/Privacy level

What shall we do with boxes that are no "settings" (don't allow interactions) but are also not shown in "basic" (eg. some boxes in system) - shall they get an icon?

[DL6ER]

So far, the settings levels (now reduced to two) were set in the web interface along - independently of FTL's flag ADVANCES_SETTING. This should probably be brought together somehow. I'm not sure how to do this best without the boxes first appearing and then disappearing again (or the other way around) as the AJAX API call will in every case have some (even it small) delay. Ideas?

[yubiuser]

I think this PR is a nice addition by reducing the overall number of "levels" and adding the "show only changed" items. This is worth to be implemented. In a subsequent step, we can think about how to deal with the "doubled" FTL and web flags and how/if we could combine them.

[yubiuser]

We should use the same symbols for "expert level" boxes on the the settings pages (currently wrench) and in "all settings" (cog)

[yubiuser]

1. We still have a few mixture of "advanced" and "expert" across various files. This should be unified.
2. We decided to call it "settings-all" > this should be reflected also by renaming "settings-advanced.js" to "settings-all.js"

[yubiuser]

Thinking about

In a subsequent step, we can think about how to deal with the "doubled" FTL and web flags and how/if we could combine them.

Why do we need this FTL flag at all? We currently use it in two places: on various setting pages to determine if at least one "setting" within a "box" has the flag and set the wrench symbol. And on "all settings" to set the cog symbol for each setting box.

My proposal: remove the flag entirely. On the setting page, manually set the wrench to the box if we think the box contains something considered "advanced/expert". On "all settings" this symbol is useless > "all settings" is only reachable if "Expert level" has been selected already. If a user is so advanced to play around in "all settings" there is no need to highlight some settings as "advanced"

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.

[DL6ER]

The last comment makes this PR depend on pi-hole/FTL#1883

[github-actions]

Conflicts have been resolved.

[PromoFaux]

Tested (both PRs) and working well. A couple of comments from my perspective (by no means mandatory for approval and up for discussion/refusal!)

On the All Settings page, after toggling to show only modified settings, the group headers are still visible if there are no modified settings within that group. Could those also be removed?

On the Local DNS Settings page (which is only visible with the Expert mode toggled), if you toggle the switch back to basic, you are left on the Local DNS Settings page but with zero options. Could a redirect to System be implemented in this case?

[rdwebdesign]

When the page is loaded, the checkbox is visible before the toggle buttons are created:

I'm adding a commit to hide it using CSS.