docs: add tubco setup runbook

CONTRIBUTING.md

@@ -5,6 +5,7 @@ This repository is the standalone productized Workdock platform.
 
 Use this file as the quick-start guide for future coders. It complements:
 - `DEPLOYMENT.md`
+- `TUBCO_SETUP.md`
 - `backend/workflows/templates/workflows/project_wiki.html`
 - `backend/workflows/templates/workflows/developer_handbook.html`
 
@@ -34,6 +35,8 @@ Rule:
 
 Do not let a customer deployment track `develop` directly.
 
+Use `TUBCO_SETUP.md` for the customer-specific bootstrap, reset, config-sync, and deploy sequence.
+
 ## Dual Remote Workflow
 This repository now has two different Git remotes with different purposes:
 - `origin`: the normal GitHub product remote