settings-dhcp: Implement copyButton to copy active DHCP leases in dnsmasq format

[DroidFreak32]

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What does this PR aim to accomplish?:

This will allow users to easily add a current lease into the static leases configuration, closer to v5 behavior.

How does this PR accomplish the above?:

• Add a new copy icon button in the DHCPLeasesTable rows
• Create a new copyLease function that is triggerred when above button is clicked
• The MAC, IP and Hostname values are fetched from the row and copied to clipboard in dnsmasq-like syntax
• Users can easily paste in the static configuration textbox

This might help solve complaints like https://www.reddit.com/r/pihole/comments/1lac7fk

Example screenshot:

Disclosure: I am not experienced with JS so I took help from gemini, but I have verified it is working in my end.

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

N/A

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[PromoFaux]

I like this idea in theory - though I currently have no way to test it due to not using my Pi-hole as a DHCP server.

Just thinking out loud here... @pi-hole/ftl-maintainers @pi-hole/web-maintainers

If the idea of this PR work, i.e the string that is generated is good enough to paste into the dhcp reservations textbox... Could the idea be further adapted to do this more directly? Maybe a "Make static" (maybe even "make unstatic") button instead of a copy that literally just adds the string directly to the setting?

It might save the ballache of coming up with a table design that works for the reservation field.

Just spitballing

[yubiuser]

If the idea of this PR work, i.e the string that is generated is good enough to paste into the dhcp reservations textbox... Could the idea be further adapted to do this more directly? Maybe a "Make static" (maybe even "make unstatic") button instead of a copy that literally just adds the string directly to the setting?

For table-to-textbox we already have such an implementation: Settings > DNS, tick/untick one of the items in the DNS server table and see the text added/removed from the collapsed "Custom DNS servers" textbox

[DroidFreak32]

Could the idea be further adapted to do this more directly? Maybe a "Make static" (maybe even "make unstatic") button instead of a copy

That would require to parse the existing list of Static DHCP configurations, find if a similar entry already exists, and only if it doesn't exist add it to the list, correct?

But it might break existing power users setup who used a more advanced dnsmasq entry rather than just hwaddr:ipaddr:hostname which this PR creates.

The intention of adding the copy option is because the current 6.x release already moved to a more flexible advanced method for power users to add dnsmasq entries, which might break if pihole directly adds entries (like the behavior in 5.x). Copying will just make it much easier to add entries while allowing power users to modify the syntax to their needs.

[PromoFaux]

But it might break existing power users setup who used a more advanced dnsmasq entry rather than just hwaddr:ipaddr:hostname which this PR creates.

So my thought here is that if a valid line always starts with hwaddr - could we not "pair" table entires to the static list based only on that? Once it was added to the static list - the user could then add advanced things to it if they really wanted - the key information would still be shown in the current lease table in the same way it currently would be.

Maybe, I don't know... I haven't used DHCP on Pi-hole/dnsmasq in such a long time that I'm probably very out of touch with how things work

[DL6ER]

Please see my alternative suggestion here: #3565