public Optional<Symbol> findSymbol(Symbol symbol) {
        return findSymbol(symbol.getScope(), symbol.getType(), symbol.getShortIdentifier());
    }
Searches for the specified symbol in the index.

@param symbol The symbol to find, should be UNRESOLVED
@return An Optional containing the found symbol, or an empty Optional if the symbol is not found.
integration/schema-language-server/language-server/src/main/java/ai/vespa/schemals/index/SchemaIndex.java