fix(schedule): allow explicit label visibility bypass

[JohnVillalovos]

Add an explicit skipVisibilityChecks argument to
SlotLabelFactory::Format for callers that have already authorized reservation details. Keep the default path unchanged and keep NullSlotLabelFactory fail-closed.

Assisted-by: Codex:GPT-5

[Copilot]

Pull request overview

This PR extends the schedule label formatting API by adding an explicit skipVisibilityChecks argument to SlotLabelFactory::Format() for trusted callers that have already authorized access to reservation details (e.g., authenticated subscription feeds). The default behavior remains unchanged, and NullSlotLabelFactory continues to return an empty label.

Changes:

• Add skipVisibilityChecks (default false) to SlotLabelFactory::Format() and to NullSlotLabelFactory::Format().
• Keep user-detail redaction enforced when privacy.hide.user.details is enabled (now applies to {email}, {phone}, {organization}, {position}, {participants}, {invitees} as well).
• Add PHPUnit coverage ensuring the bypass works when explicitly requested, while still redacting user tokens and keeping NullSlotLabelFactory fail-closed.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
lib/Application/Schedule/SlotLabelFactory.php	Adds the skipVisibilityChecks parameter and ensures user-detail redaction is consistently applied across all user-related tokens.
tests/Presenters/CalendarExportPresenterTest.php	Adds tests validating explicit visibility bypass behavior and fail-closed behavior for NullSlotLabelFactory.