Add global Wine preferences tab

Phase 3 of the Wine/Proton stage (decisions 6, 9, 13, 19 in docs/testing/wine-proton.md): a global-only Wine tab modeled on the Pronunciation page, with the controller-only checkbox and a typed editable program list. Wine values flow through the preferences protocol so a global Apply reaches the live Wine settings from Phase 2 with no reader restart. Entries are validated as edited and named in-tab, blocking Apply until fixed; case-insensitive duplicates collapse. Per-application preferences expose no Wine editing and an app-scoped Apply cannot change the governing list.

internal/preferences/protocol.go

@@ -18,6 +18,9 @@ import (
 type Values struct {
 	StructuralNavigationTriggersFocusMode bool
 
+	// Wine is global-only: it is edited only in global preferences, and
+	// application preferences carry the base values through unchanged.
+	Wine                      config.WineSettings
 	Pronunciations            []config.PronunciationEntry
 	TextAttributes            config.TextAttributeSettings
 	OCR                       config.OCRSettings