Refactor POS tab: separate visibility and eligibility logic while removing POS as a tab i2 feature flag#16173

jaclync merged 11 commits intotrunkwoocommerce/woocommerce-ios:trunkfrom

backlog/WOOMOB-869-remove-pos-tab-i2-feature-flag-with-refactoringwoocommerce/woocommerce-ios:backlog/WOOMOB-869-remove-pos-tab-i2-feature-flag-with-refactoringCopy head branch name to clipboard