[Bug] ApiSourceEnum.IMPORT_YAPI has no backend implementation (dead import option) #7594

Symptom

ApiSourceEnum defines IMPORT_YAPI("import_yapi", 4) (shenyu-common/.../enums/ApiSourceEnum.java:48), and the admin UI offers an "import yapi" choice, but there is no backend implementation of YAPI import anywhere in the codebase (no YapiImport*, no YapiDoc*, no YapiImportService/Controller). Selecting the YAPI source leads nowhere.

Evidence

• Repo-wide search for yapi (case-insensitive, excluding unrelated ProxyApiKey / queryByApiId substring hits) returns only the enum constant and a doc comment in ApiDTO ("4-import yapi"); no import logic.
• ApiSourceEnum.IMPORT_YAPI is never read by any import branch (the only import branches are swagger import / annotation generation).

Impact

A documented / UI-exposed capability is non-functional; users may configure an import source that silently does nothing.

Options

• Implement YAPI import: fetch the YAPI project JSON, map it to ApiDocRegisterDTO / MetaDataRegisterDTO (reuse SwaggerDocParser or add a new YapiDocParser).
• Or remove IMPORT_YAPI and the UI option to avoid advertising an unimplemented feature.

Related

• [Refactor] Remove dead API-doc viewer (ApiDocController + DOC_DEFINITION_MAP) and keep the live swagger→MCP publish pipeline #7592 (dead DOC_DEFINITION_MAP / apidoc viewer removal, same API-doc area).