refactor!: refactor installer internals and add new Package class methods (#1523)

This contains the following changes:
1) `Package:install()` now accepts a second, optional, callback argument which is called when installation finishes
   (successfully or not).
2) Adds a `Package:is_installing()` method.

This contains the following breaking changes:
1) `Package:install()` will now error when called while an installation is already ongoing. Use the new
   `Package:is_installing()` method to check whether an installation is already running.

This also refactors large portions of the tests by removing test globals, removing async_test, and adding the
`mason-test` Lua module instead. Test helpers via globals are problematic to work with due to not being detected through
tools like the Lua language server without additional configuration. This has been replaced with a Lua module
`mason-test`. `async_test` has also been removed in favour of explicitly making use of the `mason-core.async` API. These
changes stands for a significant portion of the diff.

1 files changed, 0 insertions, 219 deletions

diff --git a/lua/mason-core/installer/registry/init.lua b/lua/mason-core/installer/registry/init.lua
deleted file mode 100644
index 7376db86..00000000
--- a/lua/mason-core/installer/registry/init.lua
+++ /dev/null
@@ -1,219 +0,0 @@
-local Optional = require "mason-core.optional"
-local Purl = require "mason-core.purl"
-local Result = require "mason-core.result"
-local _ = require "mason-core.functional"
-local a = require "mason-core.async"
-local link = require "mason-core.installer.registry.link"
-local log = require "mason-core.log"
-local schemas = require "mason-core.installer.registry.schemas"
-local util = require "mason-core.installer.registry.util"
-
-local M = {}
-
----@type table<RegistryPackageSpecSchema, boolean>
-M.SCHEMA_CAP = _.set_of {
-    "registry+v1",
-}
-
----@type table<string, InstallerProvider>
-local PROVIDERS = {}
-
----@param id string
----@param provider InstallerProvider
-function M.register_provider(id, provider)
-    PROVIDERS[id] = provider
-end
-
-M.register_provider("cargo", _.lazy_require "mason-core.installer.registry.providers.cargo")
-M.register_provider("composer", _.lazy_require "mason-core.installer.registry.providers.composer")
-M.register_provider("gem", _.lazy_require "mason-core.installer.registry.providers.gem")
-M.register_provider("generic", _.lazy_require "mason-core.installer.registry.providers.generic")
-M.register_provider("github", _.lazy_require "mason-core.installer.registry.providers.github")
-M.register_provider("golang", _.lazy_require "mason-core.installer.registry.providers.golang")
-M.register_provider("luarocks", _.lazy_require "mason-core.installer.registry.providers.luarocks")
-M.register_provider("npm", _.lazy_require "mason-core.installer.registry.providers.npm")
-M.register_provider("nuget", _.lazy_require "mason-core.installer.registry.providers.nuget")
-M.register_provider("opam", _.lazy_require "mason-core.installer.registry.providers.opam")
-M.register_provider("openvsx", _.lazy_require "mason-core.installer.registry.providers.openvsx")
-M.register_provider("pypi", _.lazy_require "mason-core.installer.registry.providers.pypi")
-M.register_provider("mason", _.lazy_require "mason-core.installer.registry.providers.mason")
-
----@param purl Purl
-function M.get_provider(purl)
-    return Optional.of_nilable(PROVIDERS[purl.type]):ok_or(("Unknown purl type: %s"):format(purl.type))
-end
-
----@class InstallerProvider
----@field parse fun(source: RegistryPackageSource, purl: Purl, opts: PackageInstallOpts): Result
----@field install async fun(ctx: InstallContext, source: ParsedPackageSource, purl: Purl): Result
----@field get_versions async fun(purl: Purl, source: RegistryPackageSource): Result # Result<string[]>
-
----@class ParsedPackageSource
-
----Upserts {dst} with contents of {src}. List table values will be merged, with contents of {src} prepended.
----@param dst table
----@param src table
-local function upsert(dst, src)
-    for k, v in pairs(src) do
-        if type(v) == "table" then
-            if _.is_list(v) then
-                dst[k] = _.concat(v, dst[k] or {})
-            else
-                dst[k] = upsert(dst[k] or {}, src[k])
-            end
-        else
-            dst[k] = v
-        end
-    end
-    return dst
-end
-
----@param source RegistryPackageSource
----@param version string
-local function coalesce_source(source, version)