feat(media-supply): add media resource supply marketplace

Introduce an end-to-end media-supply feature: tenant-side resource sync
service/worker backed by a Meijiequan supplier client, ops-side management
APIs, and admin/ops web views for resources, orders, favorites and
submission. Adds a shared digitocr helper, MediaSupply config blocks for
tenant and ops, shared types, and migrations for supplier media resources,
price overrides, customer visibility and order refunds.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

server/go.mod

@@ -27,6 +27,7 @@ require (
 	github.com/stretchr/testify v1.11.1
 	github.com/volcengine/volcengine-go-sdk v1.2.22
 	github.com/xuri/excelize/v2 v2.8.1
+	github.com/yuin/goldmark v1.8.2
 	go.uber.org/zap v1.27.0
 	golang.org/x/crypto v0.46.0
 	golang.org/x/image v0.38.0