ci: one-function-per-file at max_lines = 1 — packages/python/dirsql/resolve_config_extensions.py #1079

Second and last step of the packages/python/dirsql lane of the #1020 ratchet endgame. Sibling of #1066, which covers resolve_extension.py.

At max_lines = 1 the gate flags three of the four module-scope functions in dirsql/resolve_config_extensions.py:

resolve_config_extensions.py:42: `_load_extension_entries` runs 11 lines, and `_load_toml_module` already holds this file
resolve_config_extensions.py:63: `_has_bare_name` runs 6 lines, and `_load_toml_module` already holds this file
resolve_config_extensions.py:72: `resolve_config_extension_specs` runs 7 lines, and `_load_toml_module` already holds this file

The holder is a free choice, so keep the module’s named export resolve_config_extension_specs in the file and move the three helpers out:

Stacked on #1066’s branch (claude/1066-p1-resolve-extension): the new has_bare_name module imports is_bare_name, which #1066 moves to dirsql/is_bare_name.py.

resolve_configs_extension_specs.py imports _has_bare_name and _load_extension_entries and gets repointed at the new modules.

Out of scope, per #1020: no testing-conventions.toml edit. The committed ceiling stays at 12; a separate final PR deletes the key once every lane is clean.

No behavior change, no public API change. Exemptions stay at zero.