add testnet4 support

[0xf0xx0]

this adds testnet4 alongside testnet3, but since testnet3 is deprecated, should its info be replaced with testnet4 info? also, have i missed anything?

closes #666, and also has the side effect of fixing #664
closes #664 (keyword for github)

[schildbach]

This has a lot of code reformatting, making it difficult to locate the actual changes to review.

[schildbach]

but since testnet3 is deprecated, should its info be replaced with testnet4 info?

I think testnet3 should be supported alongside testnet4 for a while. I'm still using it. as it's a good way to smoke test in extreme conditions.

[0xf0xx0]

This has a lot of code reformatting, making it difficult to locate the actual changes to review.

mm yea, i've been trying to reduce the formatting changes but i have no clue what @janoside is using so i can keep it consistent x3
ill go back and manually un-format uwu

[0xf0xx0]

THERE
i hate whitespace bro istg
all formatting changes removed

[schildbach]

I wonder why do you change the testnet3 coin color at this point? I think both testnet3 & 4 could use the same color green.

And also I wonder if this also changes the color of the favicon, which follows coin color as well in order to visually distinguish browser tabs.

[0xf0xx0]

i picked a color between mainnet and testnet to make the explorer icons visually distinct, but now that i look closer it doesnt look like these colors are even used. the favicons are hardcoded in their respective .svgs, and the tab color is hardcoded here: https://github.com/janoside/btc-rpc-explorer/blob/153aa0ae7f902562bd1cfa2bbcea4c00026e5aef/views/layout.pug#L49C45-L50C1

[0xf0xx0]

bringing this back up, @janoside what do you use to generate the site favicons? is copy-pasting /public/img/test to /public/img/testnet4 fine? bitcoind plans to drop testnet3 soon, so we should try and get 4 added and a release made: bitcoin/bitcoin#31975

[holguinvictor]

Listen to me.

[0xf0xx0]

@janoside bumping, if this pr is too large to review atm should i extract the fix for #664 into another pr for merging?

[schildbach]

I've marked one more formatting change for removal from this PR. Maybe this would make reviewing easier.

[schildbach]

@janoside bumping, if this pr is too large to review atm should i extract the fix for #664 into another pr for merging?

In general yes, please don't mix separate issues into one PR. It sill (sometimes dramatically) lessen the chance for someone looking at it and eventually merge it.

[0xf0xx0]

In general yes, please don't mix separate issues into one PR. It sill (sometimes dramatically) lessen the chance for someone looking at it and eventually merge it.

yea, the issue is its not exactly separate x3 fixing 664 was a side effect of getting testnet4 support working