Because ext-phar sucks, tmp gets spammed by cache files for every thread when loading files from the phar on the fly.
Instead, we convert the `.phar` into a decompressed `.tar` in the tmp directory and require files from inside it. Surprisingly, this works because `ext-phar` supports `tar` and `zip` natively. No stream wrapper is required, as the `PocketMine.php` bootstrap loads files relative to its location, so the cache is automatically used for everything.
To be honest I would rather get rid of phars entirely, but they are still the easiest way to have PhpStorm load PocketMine-MP API information for now, and the alternatives are more complicated and inconvenient.
### Caveats
Everywhere that previously used `new Phar(Phar::running(false))` in the core code needs to be updated to use `PharData` for this to work correctly. Plugins don't need to do anything.
### Why not just use `Phar::decompressFiles()`?
This requires setting `phar.readonly` to `0`, which is a security issue. Technically, we could have used a subprocess to do this, but it just didn't seem right.
### WTF? `phar://` can be used on `tar` files???
Yup. I was just as surprised to find out that `require` works in such contexts.
### Relevant issues
- Closes#6214
## Changes
### API changes
None.
### Behavioural changes
Server startup will be slightly slower, as the phar has to decompress and convert itself into a `.tar`. However, testing showed that this generally takes less than 200 ms, so it should be barely noticeable.
## Backwards compatibility
No BC issues.
## Tests
Locally tested and the CI will also verify
this is much easier to use than devtools, and allows us to make additional specializations for PM build that would otherwise just be a colossal pain in the ass.
