feat(dashboard): CUST-WP-0019 — Repository nav section, config.js cleanup

T01: Restructure nav — "Repos" → collapsible "Repository" section with
     Repo Sync, SBOM, Debt as sub-pages; Debt moved out of Workstreams
T02: workstream-dod.md migrated from inline const API to config.js import
T03: todo.md suggestion filter (done in previous commit)

Closes CUST-WP-0019. Resolves UI suggestion c2fc284a.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

dashboard/src/policy/workstream-dod.md

@@ -3,7 +3,7 @@ title: Workstream Definition of Done
 ---
 
 ```js
-const API = "http://127.0.0.1:8000";
+import {API} from "../components/config.js";
 ```
 
 ```js