[harness] Wire factory discovery via .claude symlink and gitignore

.claude -> .agents so Claude Code discovers the skills; un-ignore .claude and ignore only .agents/settings.local.json.

Author: glentner

.claude

@@ -0,0 +1 @@
+.agents

.gitignore

@@ -46,7 +46,9 @@ htmlcov/
 .env.local
 
 # Assistant / tooling scratch
-.claude/
+#   `.claude` is a tracked symlink -> `.agents` (the documentation factory), so it is NOT
+#   ignored. Only genuinely personal Claude Code settings are ignored:
+.agents/settings.local.json
 .warp/
 
 # Project-local drafts not for publication