Split shared GRUB policy into a common fragment

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

config/redbear-full-grub.toml

@@ -7,13 +7,4 @@
 # GRUB presents a menu and chainloads the Redox bootloader.
 # Requires: efi_partition_size >= 8 (16 recommended for GRUB + Redox bootloader + margin)
 
-include = ["redbear-full.toml"]
+include = ["redbear-full.toml", "redbear-grub.toml"]
-
-[general]
-bootloader = "grub"
-efi_partition_size = 16
-
-# GRUB recipe must be built before the installer runs.
-# Including it here ensures `make all` builds it as part of the normal package set.
-[packages]
-grub = {}

config/redbear-grub.toml

@@ -0,0 +1,11 @@
+# Red Bear OS shared GRUB policy fragment
+# Use with any redbear-* profile to make GRUB first-class in installer flows.
+
+[general]
+bootloader = "grub"
+# Keep ESP large enough for GRUB EFI image + Red Bear bootloader + future growth.
+efi_partition_size = 16
+
+[packages]
+# Ensure GRUB artifacts are present for installer-native chainload layout.
+grub = {}