Brand Hydra OS image and add custom Fastfetch summary

hydra/image.py

@@ -251,6 +251,21 @@ def enable_user_audio(root):
         raise ImageError('Cannot enable user audio sockets: ' + result.stderr.strip())
 
 
+def brand_os_release(root):
+    """Override derivative identity while retaining packaged Gentoo release fields."""
+    release = root_path(root, 'etc/os-release')
+    if not release.is_file():
+        release = root_path(root, 'usr/lib/os-release')
+    original = release.read_text() if release.is_file() else ''
+    retained = [line for line in original.splitlines()
+                if not re.match(r'^(NAME|PRETTY_NAME|ID|ID_LIKE)=', line)]
+    retained += ['NAME="Hydra OS"', 'PRETTY_NAME="Hydra OS"',
+                 'ID=hydra-os', 'ID_LIKE=gentoo']
+    # Gentoo links /etc/os-release to its packaged file; keep that file intact.
+    remove(root, 'etc/os-release')
+    write(root, 'etc/os-release', '\n'.join(retained) + '\n')
+
+
 def configure_rootfs(root, source):
     root, source = Path(root), Path(source)
     # Refuse incomplete integrations before changing the exported copy.
@@ -264,6 +279,7 @@ def configure_rootfs(root, source):
         alias.symlink_to(kernel.name)
     sanitize_rootfs(root)
     copy_overlay(root, source / 'image/rootfs')
+    brand_os_release(root)
     write(root, 'etc/hydra/live-mode/dracut.conf', (source / 'image/dracut.conf').read_text())
     root_path(root, 'etc/hydra/live-mode/dracut.conf.d').mkdir()
     package = root_path(root, 'usr/lib/hydra/hydra')