* lsp: handle kinds not specified in protocol
fix: #12200
If the client set "symbolKind.valueSet",
the client must handle it properly even if it receives a value outside the specification.
* test: add lsp.util.{get_completion_item_kind_name, get_symbol_kind_name} test case
* lsp: make lsp.util.{get_completion_item_kind_name, get_symbol_kind_name} private