static SourceContextLoader createLineBasedLoader(int defaultCodeLines) {
        return new DefaultSourceLoader(defaultCodeLines, null);
    }
Load context and include {@code defaultCodeLines} lines leading up to the target line.

@param defaultCodeLines Number of leading lines to include leading up to the target. Must be greater than 0.
@return Returns the loader.
@throws IllegalArgumentException if {@code defaultCodeLines} is less than 1.
smithy-model/src/main/java/software/amazon/smithy/model/loader/sourcecontext/SourceContextLoader.java