- Add global_margin_type field in res.config.settings
* Options: 'markup' (default) or 'margin' (commercial margin)
* Determines how global min/max percentages are interpreted
- Refactor _apply_global_margin_limits():
* Now receives price instead of margin percentage
* Calculates min/max prices based on global_margin_type
* Returns adjusted price instead of adjusted margin
* Supports both markup and commercial margin formulas
- Update _compute_price() to apply limits after price calculation
- Update res_config_settings_views.xml to show global_margin_type selector
- Update help texts with examples for both calculation methods
- Add 2 new tests to validate global limits with commercial margin type:
* test_global_minimum_with_commercial_margin_type
* test_global_maximum_with_commercial_margin_type
- All 13 tests passing (11 existing + 2 new)
Example with global min 25%:
- Markup: Min price = Cost × 1.25
- Commercial Margin: Min price = Cost / 0.75 (ensures 25% margin on PVP)