Gate READY on download completion; move audio to ~/.radiantwave/audio

State machine now uses DOWNLOADING_ASSETS before READY. Downloads closing
the DownloadDone channel signals checkState() to proceed. Download failure
sets downloadFailed flag which prevents READY. Audio files moved from
~/.local/share/rhemawave/audio to ~/.radiantwave/audio/.

Regression tests in application_test.go (linux build-tagged due to
network package D-Bus init). Version 0.6.

internal/page/home.go

@@ -13,7 +13,7 @@ import (
 	"rhemawavetech.com/rhemawave/internal/shaderManager"
 )
 
-var GitVersion = "Audio-Bug-Fix 0.5"
+var GitVersion = "Audio-Bug-Fix 0.6"
 
 type Home struct {
 	Base
@@ -31,6 +31,7 @@ type Home struct {
 	hasLicenseInfo       bool
 	baseFontSize         int
 	isDownloadComplete   bool
+	downloadFailed       bool
 }
 
 // Init performs basic page initialization and creation of static assets.
@@ -172,8 +173,13 @@ func (p *Home) Update(dt float32) error {
 		case progressUpdate, ok = <-p.Context.MessageChannel:
 			gotUpdate = true
 			if !ok {
-				p.setMessage("Status: READY", colors.Green)
-				p.isDownloadComplete = true
+				if p.downloadFailed {
+					p.setMessage("Download failed — restart to retry", colors.Red)
+				} else {
+					p.setMessage("Status: READY", colors.Green)
+					p.isDownloadComplete = true
+					close(p.Context.DownloadDone)
+				}
 				return nil
 			}
 		default:
@@ -187,6 +193,7 @@ drained:
 	}
 
 	if progressUpdate.Err != nil {
+		p.downloadFailed = true
 		p.setMessage(fmt.Sprintf("Error: %s", progressUpdate.Err.Error()), colors.Red)
 		return nil
 	}

internal/page/router.go

@@ -25,6 +25,7 @@ type PageCtx struct {
 	DbPtr          *gorm.DB
 	W, H           int32
 	MessageChannel chan download.DownloadStatus
+	DownloadDone   chan struct{} // closed when downloads finish (success or failure)
 	NavigateTo     func(pageType)
 	Msg            string // Message to be displayed by MessagePage
 	Inst           string // Instructions to be displayed on MessagePage

internal/page/scrollerPage.go

@@ -291,7 +291,7 @@ func (p *ScrollerPage) Init(ctx *PageCtx) error {
 		if err := p.Context.DbPtr.Where("Selected = ?", true).First(&selectedAudio).Error; err != nil {
 			selectedAudio = db.AudioFile{
 				Name:     "OriginalAudio",
-				Path:     filepath.Join(config.AssetsDir, "audio", "OriginalAudio.wav"),
+				Path:     filepath.Join(audioDir(), "OriginalAudio.wav"),
 				Selected: true,
 				Order:    0,
 			}
@@ -420,14 +420,19 @@ func (p *ScrollerPage) loadProclamations() error {
 	return nil
 }
 
-// audioPathForFrequency builds the on-disk path for a solfeggio frequency's
-// audio file, e.g. 396 -> "<AssetsDir>/audio/396Hz.wav".
-func (p *ScrollerPage) audioPathForFrequency(freq int) string {
-	config, err := db.GetConfig(p.Context.DbPtr)
+// audioDir returns the path to the audio files directory (~/.radiantwave/audio).
+func audioDir() string {
+	home, err := os.UserHomeDir()
 	if err != nil {
 		panic(err)
 	}
-	return filepath.Join(config.AssetsDir, "audio", fmt.Sprintf("%dHz.wav", freq))
+	return filepath.Join(home, ".radiantwave", "audio")
+}
+
+// audioPathForFrequency builds the on-disk path for a solfeggio frequency's
+// audio file, e.g. 396 -> "~/.radiantwave/audio/396Hz.wav".
+func (p *ScrollerPage) audioPathForFrequency(freq int) string {
+	return filepath.Join(audioDir(), fmt.Sprintf("%dHz.wav", freq))
 }
 
 // switchAudioForFrequency swaps the currently playing track to match freq.