SSH: Add managed config with Include and local config stub

Create a base SSH config that includes all files from ~/.ssh/config.d/.
This enables the work layer and local machine-specific configs to add
SSH host entries without modifying the main config file.

Also seed an empty ~/.ssh/config.d/local file (via create_ prefix) for
untracked machine-specific SSH config that neither layer manages.

Co-authored-by: Claude (claude-opus-4-6) <noreply@anthropic.com>

Author: jacobo-doist

home/dot_ssh/config

@@ -0,0 +1,4 @@
+# Managed by chezmoi — do not edit manually
+# Local/work SSH config goes in ~/.ssh/config.d/
+
+Include ~/.ssh/config.d/*

home/dot_ssh/config.d/create_local

@@ -0,0 +1,2 @@
+# Machine-specific SSH config — not managed by chezmoi
+# Edit this file directly; chezmoi will not overwrite it.