feat: App struct with New(Options) + Find() as method

App.New() creates from Options. App.Find() locates programs on PATH.
Both are struct methods — no package-level functions.
8 tests passing.

Co-Authored-By: Virgil <virgil@lethean.io>

app.go

@@ -1,7 +1,6 @@
 // SPDX-License-Identifier: EUPL-1.2
 
 // Application identity for the Core framework.
-// Based on leaanthony/sail — Name, Filename, Path.
 
 package core
 
@@ -11,32 +10,47 @@ import (
 )
 
 // App holds the application identity and optional GUI runtime.
+//
+//	app := core.App{}.New(core.NewOptions(
+//	    core.Option{Key: "name", Value: "Core CLI"},
+//	    core.Option{Key: "version", Value: "1.0.0"},
+//	))
 type App struct {
-	// Name is the human-readable application name (e.g., "Core CLI").
-	Name string
-
-	// Version is the application version string (e.g., "1.2.3").
-	Version string
-
-	// Description is a short description of the application.
+	Name        string
+	Version     string
 	Description string
+	Filename    string
+	Path        string
+	Runtime     any // GUI runtime (e.g., Wails App). Nil for CLI-only.
+}
 
-	// Filename is the executable filename (e.g., "core").
-	Filename string
-
-	// Path is the absolute path to the executable.
-	Path string
-
-	// Runtime is the GUI runtime (e.g., Wails App).
-	// Nil for CLI-only applications.
-	Runtime any
+// New creates an App from Options.
+//
+//	app := core.App{}.New(core.NewOptions(
+//	    core.Option{Key: "name", Value: "myapp"},
+//	    core.Option{Key: "version", Value: "1.0.0"},
+//	))
+func (a App) New(opts Options) App {
+	if name := opts.String("name"); name != "" {
+		a.Name = name
+	}
+	if version := opts.String("version"); version != "" {
+		a.Version = version
+	}
+	if desc := opts.String("description"); desc != "" {
+		a.Description = desc
+	}
+	if filename := opts.String("filename"); filename != "" {
+		a.Filename = filename
+	}
+	return a
 }
 
 // Find locates a program on PATH and returns a Result containing the App.
 //
-//	r := core.Find("node", "Node.js")
+//	r := core.App{}.Find("node", "Node.js")
 //	if r.OK { app := r.Value.(*App) }
-func Find(filename, name string) Result {
+func (a App) Find(filename, name string) Result {
 	path, err := exec.LookPath(filename)
 	if err != nil {
 		return Result{err, false}

app_test.go

@@ -7,14 +7,41 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-// --- App ---
+// --- App.New ---
 
-func TestApp_Good(t *testing.T) {
-	c := New(WithOptions(NewOptions(Option{Key: "name", Value: "myapp"}))).Value.(*Core)
+func TestApp_New_Good(t *testing.T) {
+	app := App{}.New(NewOptions(
+		Option{Key: "name", Value: "myapp"},
+		Option{Key: "version", Value: "1.0.0"},
+		Option{Key: "description", Value: "test app"},
+	))
+	assert.Equal(t, "myapp", app.Name)
+	assert.Equal(t, "1.0.0", app.Version)
+	assert.Equal(t, "test app", app.Description)
+}
+
+func TestApp_New_Empty_Good(t *testing.T) {
+	app := App{}.New(NewOptions())
+	assert.Equal(t, "", app.Name)
+	assert.Equal(t, "", app.Version)
+}
+
+func TestApp_New_Partial_Good(t *testing.T) {
+	app := App{}.New(NewOptions(
+		Option{Key: "name", Value: "myapp"},
+	))
+	assert.Equal(t, "myapp", app.Name)
+	assert.Equal(t, "", app.Version)
+}
+
+// --- App via Core ---
+
+func TestApp_Core_Good(t *testing.T) {
+	c := New(WithOption("name", "myapp")).Value.(*Core)
 	assert.Equal(t, "myapp", c.App().Name)
 }
 
-func TestApp_Empty_Good(t *testing.T) {
+func TestApp_Core_Empty_Good(t *testing.T) {
 	c := New().Value.(*Core)
 	assert.NotNil(t, c.App())
 	assert.Equal(t, "", c.App().Name)
@@ -26,14 +53,16 @@ func TestApp_Runtime_Good(t *testing.T) {
 	assert.NotNil(t, c.App().Runtime)
 }
 
+// --- App.Find ---
+
 func TestApp_Find_Good(t *testing.T) {
-	r := Find("go", "go")
+	r := App{}.Find("go", "go")
 	assert.True(t, r.OK)
 	app := r.Value.(*App)
 	assert.NotEmpty(t, app.Path)
 }
 
 func TestApp_Find_Bad(t *testing.T) {
-	r := Find("nonexistent-binary-xyz", "test")
+	r := App{}.Find("nonexistent-binary-xyz", "test")
 	assert.False(t, r.OK)
 }