feat: GitHub stars badge on open-source projects via shields.io

- New openSource field in project model distinguishes OS from private
- shields.io badge shows live star count for open-source projects
- SoundInbox marked as NOT open source (no badge, no stars)
- Immich Photo Manager, Cmux Resurrect, Gotify Commander, CDC Starter Kit → open source
- Stars badge hidden in print view

internal/models/cv.go

@@ -100,6 +100,7 @@ type Project struct {
 	ProjectLogo      string   `json:"projectLogo,omitempty"`      // Optional logo filename
 	LogoIndex        *int     `json:"logoIndex,omitempty"`        // Sprite sheet index (nil means no sprite)
 	GitRepoUrl       string   `json:"gitRepoUrl,omitempty"`       // Optional git repository URL for dynamic dates
+	OpenSource       bool     `json:"openSource,omitempty"`       // True if project is open source (shows stars badge)
 	Location         string   `json:"location"`
 	StartDate        string   `json:"startDate,omitempty"`        // Optional static start date
 	Current          bool     `json:"current"`

internal/models/cv/cv.go

@@ -105,6 +105,7 @@ type Project struct {
 	ProjectLogo      string   `json:"projectLogo,omitempty"`      // Optional logo filename
 	LogoIndex        *int     `json:"logoIndex,omitempty"`        // Sprite sheet index (nil means no sprite)
 	GitRepoUrl       string   `json:"gitRepoUrl,omitempty"`       // Optional git repository URL for dynamic dates
+	OpenSource       bool     `json:"openSource,omitempty"`       // True if project is open source (shows stars badge)
 	Location         string   `json:"location"`
 	StartDate        string   `json:"startDate,omitempty"`        // Optional static start date
 	Current          bool     `json:"current"`