feat(desktop): compress packaged app with xz by default

[bartlomieju]

Packaging is now compressed by default. Building on the self-extracting
support that was added recently, the --compress flag accepts xz,
zstd, and none, and now defaults to xz so a bare deno desktop
ships a compressed app. xz is decompressed by the system tar
everywhere, while zstd is smaller and faster but needs the zstd tool
at runtime. Passing --compress none ships the app uncompressed. The
previous lzma alias is dropped (it normalized to xz anyway).

Added unit tests covering the new default, explicit compressor selection,
the none opt-out, and the bare --compress form.

The webview-default change that previously lived here has been split out
into #35442.

[sigmaSd]

I understand the desire to get a low size, but the compressed by default will make users have many random stuff extracted in their disk (even if they're just experimenting),
just wanted to point this downside , maybe if it was like under a deno namespace it would be less problematic like ~/.local/share/deno-desktop/$ids but I don't know if that's allowed by the xdg spec

[sigmaSd]

if you're going with this default it would be great if you at least provide an env variable for this so I don't have to pass a flag each time, compression is an explicit choice when I'm done with the app and going to distribute it to the user maybe used only in ci even