feat: add the infrastructure to support "system" packages (#2085)

This enables `mason.nvim` to start managing certain packages that:

1) are not suitable for the core registry
2) should not surface in existing APIs and UIs

1 files changed, 8 insertions, 0 deletions

diff --git a/doc/mason.txt b/doc/mason.txt
index d4a95818..e751a94b 100644
--- a/doc/mason.txt
+++ b/doc/mason.txt
@@ -250,6 +250,14 @@ Example:
             "github:mason-org/mason-registry",
         },
 
+        ---@since 2.3.0
+        -- [Advanced setting]
+        -- The registries to source system packages from. Accepts multiple entries. Should a package with the same name exist in
+        -- multiple registries, the registry listed first will be used.
+        system_registries = {
+            "github:mason-org/mason-system-registry",
+        },
+
         ---@since 1.0.0
         -- The provider implementations to use for resolving supplementary package metadata (e.g., all available versions).
         -- Accepts multiple entries, where later entries will be used as fallback should prior providers fail.