Wire kebab_parse_code::is_generated_file and is_oversized into
FsSourceConnector::scan_with_skips. Files that pass gitignore/builtin/
kebabignore matching are now checked for generated-file markers
(config-gated via ingest.code.skip_generated_header) and byte/line caps
(ingest.code.max_file_bytes / max_file_lines). FsScanSkips gains
skipped_generated + skipped_size_exceeded counters; kebab-app threads
them into IngestReport. Also fixes a pre-existing clippy::derivable_impls
warning in IngestCfg. Three new connector tests cover all three paths.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>