Some deps.* keys have no config home yet

Index: Known gaps, closed

Status (2026-10-31): CLOSED (archive). The dependency settings reachable only from the CLI were --follow-deps, --search-path and --ld-library-path on compare and dump. Each now has a config home: deps.follow, deps.search_paths and deps.ld_library_path. Each has a registry row (architecture/option-vocabulary.yaml). The two non-core keys also have a --set path and a typed config_overrides channel on CompareRequest/DumpRequest; deps.follow backs a core flag, so those refuse it, naming --follow-deps. The flags stay and win. deps.root (deps compare/deps tree --root) gets no key, since it is the operand of the deps commands, which read no .abicheck.yml. A directory/package compare did not apply the walk at all until the follow-up fix. Tests: tests/test_config_run_input_homes.py.