Package run targets should depend on Aegisub

[guijan]

We have Meson run targets to make installers and the like such as this one:

Aegisub/packages/meson.build

Lines 7 to 8 in e21e32e

	run_target('win-installer',
	command: [installer_setup, meson.project_build_root(), meson.project_source_root()])

However, they don't depend on the targets they're packaging. This means Meson can't automatically rebuild them when their dependencies are modified, and producing installers isn't as simple as this:

meson setup build && meson compile -C build win-installer

Instead, because the dependency on the rest of Aegisub is missing, it looks more like this:

meson setup build && meson compile -C build && meson compile -C build win-installer

And you have to remember to rerun meson compile -C build after any changes if you want to make a new installer.

Ideally, these run targets would be reviewed and changed to look more like this:

    run_target('win-installer',
               command: [installer_setup, meson.project_build_root(), meson.project_source_root()],
               depends: [aegisub_exe, docs, whatever])