ENG-912: /resources/configure/:id in React

📝 Description

/resources/configure/:resourceName renders in React: rename, delete, and the roles tab. The CLJS panel stays until ENG-922.

📣 User-facing impact

The Configure Resource page stays on the page after a role delete, explains why a resource with roles cannot be deleted, and shows "Resource not found" for an unknown name.

🔗 Related Issue

ENG-912

🚀 Type of Change

• ✨ New feature (non-breaking change which adds functionality)

📋 Changes Made

• New route above the catch-all, admin only. Quirks Q4 to Q10 fixed.
• Data Masking "configure" link goes to /roles/:name/configure; it passed a role name to the resource route.
• CLJS add_role/main.cljs loads the connection metadata on mount. The CLJS configure page used to load it; without it, Add New Role from the React page shows no credential fields.
• Roles tab: Test Connection shows only on the types the gateway can test, as in the /resources list. CLJS showed it on every row, and the gateway answered 400 (matrix Q36).

🧪 Testing

📄 Additional Notes

Low risk: webapp only, no gateway change.

Known gap, same as origin/main: a resource whose only roles are sidecar mirrors shows no roles, so Delete still reaches the gateway's 403. The webapp cannot count those roles (GET /connections leaves mirrors out). The /resources list hides such a resource; only a typed URL reaches it.