feat: read platform launchers in verify and packs

A names_searched list is one place the launcher fills with the first name it finds, so a core file it would never open once another name of the list is held is not reported missing. A place no declared file and no packed core file fills receives, under the launcher's name, a file the core accepts by content. The layer is applied inside find_undeclared_files, which verify and the pack builder both read, and a test reads their source to keep it there.

wiki/adding-a-platform.md

@@ -283,6 +283,23 @@ they copy, with `$bios_path` as the framework names it. In both, every line
 that names the BIOS directory must match a known construct, else the scrape
 stops with `LauncherPatternMissing`.
 
+`verify.py` and the pack builder read the records through one function,
+`LauncherLayer.settle()` in `scripts/launchers.py`, applied inside the
+cross-reference both of them consume. A `names_searched` list is one place:
+the names are tried in order and one held file fills it, so a core file the
+launcher would never open once another name of the list is there is not
+reported missing. A `fixed_name` or `core_option` name is a place of its own.
+Only a record that applies without condition settles the core's own name: a
+core option the user may never set, or a record tied to one system, leaves
+the core's default in use elsewhere.
+A place that no declared file and no packed core file fills receives, under
+the launcher's name, a file the core accepts: the file the collection knows
+under that name when the core takes its content, otherwise the copy held for
+the core entry read under that name. Records that only hand over a directory
+(`passes_path`, `scans_dir`) or copy a file the platform already names
+(`links`, `copies`) place nothing, and a `search_dir` the code describes
+rather than names ("directory of the Chihiro BIOS found") is skipped.
+
 ### Inheritance
 
 If the new platform inherits from an existing one (e.g. Lakka inherits RetroArch),

wiki/testing-guide.md

@@ -39,7 +39,7 @@ Every module in `tests/`, by the area it guards.
 |------|----------|---------|
 | Core regression suites | synthetic | `test_e2e`, `test_audit_regressions` |
 | File resolution and identity | synthetic + collection | `test_adler32_resolution`, `test_agnostic_scan`, `test_agnostic_scan_mode`, `test_agnostic_scope`, `test_agnostic_substitute`, `test_archive_choice`, `test_bios_companions`, `test_bundled_identity`, `test_casefold_cache`, `test_db_aliases`, `test_declared_names`, `test_derivations`, `test_directory_entries`, `test_extra_identity`, `test_foreign_tree`, `test_foreign_tree_names`, `test_frontend_digest`, `test_game_data_homonyms`, `test_hashing`, `test_identity`, `test_md5_pack_context`, `test_name_tiebreak`, `test_nec_filing`, `test_owner_resolution`, `test_path_suffix`, `test_resolution_evidence`, `test_shipped_content`, `test_twin_declarations`, `test_validated_choice`, `test_variant_choice`, `test_variant_identity`, `test_zipped_member` |
-| Verification, cross-reference and profile checks | synthetic + profiles | `test_crypto_aes`, `test_crypto_unique_data`, `test_crypto_verify`, `test_case_insensitive_platforms`, `test_checks_have_values`, `test_core_file_fills_declaration`, `test_cross_reference_sources`, `test_file_consumers`, `test_fileless_audit`, `test_gap_settlement`, `test_hidden_extras`, `test_native_mode`, `test_no_case_collisions`, `test_path_conflict_status`, `test_path_null_copies`, `test_profile_checks`, `test_romm_hash_rule`, `test_shared_groups`, `test_standalone_mode`, `test_undeclared_dedup`, `test_unplaced_extras`, `test_validation_scope`, `test_verify_all_dir`, `test_verify_emulator_evidence`, `test_verify_listing`, `test_verify_pack_choice` |
+| Verification, cross-reference and profile checks | synthetic + profiles | `test_crypto_aes`, `test_crypto_unique_data`, `test_crypto_verify`, `test_case_insensitive_platforms`, `test_checks_have_values`, `test_core_file_fills_declaration`, `test_cross_reference_sources`, `test_file_consumers`, `test_fileless_audit`, `test_gap_settlement`, `test_hidden_extras`, `test_launcher_layer`, `test_native_mode`, `test_no_case_collisions`, `test_path_conflict_status`, `test_path_null_copies`, `test_profile_checks`, `test_romm_hash_rule`, `test_shared_groups`, `test_standalone_mode`, `test_undeclared_dedup`, `test_unplaced_extras`, `test_validation_scope`, `test_verify_all_dir`, `test_verify_emulator_evidence`, `test_verify_listing`, `test_verify_pack_choice` |
 | Packs and manifests | synthetic + real packs | `test_artifact_lock`, `test_atomic_artifacts`, `test_batocera_cores`, `test_deterministic_zip`, `test_emulator_pack_counts`, `test_finalize_pack_names`, `test_large_file_cache`, `test_libretro_layout`, `test_manifest_entry`, `test_pack_conformance_dirs`, `test_pack_counts`, `test_pack_failures`, `test_pack_file_names`, `test_pack_grouping`, `test_pack_integrity`, `test_pack_member_identity`, `test_pack_readme`, `test_platform_inheritance`, `test_platform_keys`, `test_required_only_archives`, `test_required_only_twins`, `test_split_extras`, `test_split_names`, `test_split_pack`, `test_system_pack_extras`, `test_system_pack_parity`, `test_torrentzip`, `test_which_pack` |
 | Slots and regions | synthetic + profiles | `test_region`, `test_region_agnostic_scan`, `test_region_groups`, `test_region_held`, `test_region_platform_index`, `test_region_required_only`, `test_slot`, `test_slots`, `test_slots_shipped_file` |
 | Hardware targets and systems | synthetic + target files | `test_extract_targets`, `test_lakka_targets`, `test_libretro_slugs`, `test_system_ids`, `test_system_selection`, `test_target_names`, `test_target_scrapers`, `test_target_systems`, `test_target_verify` |