T1.8: Delete empty src/core; move version to src/app

Move version.go from src/core to src/app to prepare for deleting the
now-empty src/core package. Update all imports and build script
references to use src/app.Version instead of src/core.Version.

Fix import aliasing conflict between Fyne's desktop package and our
platform/desktop package by aliasing Fyne imports as fyneapp and
fynedesktop.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

src/app/version.go

@@ -1,4 +1,4 @@
-package core
+package app
 
 // Version is the application version shown in the GUI and used by build
 // scripts in artifact names. It is a var rather than a const so release builds

src/core/model.go

@@ -1 +0,0 @@
-package core

src/core/paths.go

@@ -1 +0,0 @@
-package core

src/core/store.go

@@ -1 +0,0 @@
-package core

src/core/store_test.go

@@ -1 +0,0 @@
-package core

src/gui/app.go

@@ -13,7 +13,7 @@ import (
 	"time"
 
 	"gitea.mixdep.ru/mix/gosentry/assets"
-	"gitea.mixdep.ru/mix/gosentry/src/core"
+	"gitea.mixdep.ru/mix/gosentry/src/app"
 	"gitea.mixdep.ru/mix/gosentry/src/domain"
 	"gitea.mixdep.ru/mix/gosentry/src/platform/autostart"
 	"gitea.mixdep.ru/mix/gosentry/src/platform/desktop"
@@ -22,10 +22,10 @@ import (
 	"gitea.mixdep.ru/mix/gosentry/src/storage"
 
 	"fyne.io/fyne/v2"
-	"fyne.io/fyne/v2/app"
+	fyneapp "fyne.io/fyne/v2/app"
 	"fyne.io/fyne/v2/container"
 	"fyne.io/fyne/v2/dialog"
-	"fyne.io/fyne/v2/driver/desktop"
+	fynedesktop "fyne.io/fyne/v2/driver/desktop"
 	"fyne.io/fyne/v2/layout"
 	"fyne.io/fyne/v2/theme"
 	"fyne.io/fyne/v2/widget"
@@ -60,10 +60,10 @@ func Run(startInTray bool) {
 
 	// A stable app ID lets Fyne persist desktop preferences consistently across
 	// launches and gives tray/window integration a predictable identity.
-	a := app.NewWithID(appID)
+	a := fyneapp.NewWithID(appID)
 	a.SetIcon(loadAppIcon())
 
-	w := a.NewWindow("GoSentry " + core.Version)
+	w := a.NewWindow("GoSentry " + app.Version)
 	configureSystemTray(a, w)
 	w.Resize(fyne.NewSize(1120, 720))
 	content, recordStartup := newMainView(w)
@@ -91,7 +91,7 @@ func loadAppIcon() fyne.Resource {
 }
 
 func configureSystemTray(a fyne.App, w fyne.Window) {
-	desk, ok := a.(desktop.App)
+	desk, ok := a.(fynedesktop.App)
 	if !ok {
 		// Not every Fyne driver exposes desktop tray features. Returning silently
 		// keeps the same binary usable on platforms or sessions without a tray.
@@ -1015,7 +1015,7 @@ func settingsView(w fyne.Window, store *storage.Store, jobs *[]job) fyne.CanvasO
 		settingsStatus,
 		widget.NewSeparator(),
 		widget.NewLabelWithStyle("About", fyne.TextAlignLeading, fyne.TextStyle{Bold: true}),
-		settingsRow("GoSentry", widget.NewLabel(core.Version)),
+		settingsRow("GoSentry", widget.NewLabel(app.Version)),
 		settingsRow("Go", widget.NewLabel(runtime.Version())),
 		settingsRow("Fyne", widget.NewLabel(fyneVersion())),
 		settingsRow("Repository", widget.NewHyperlink(projectRepositoryURL, mustParseURL(projectRepositoryURL))),