Add themes selector

Downterm/CommandNotch/Models/TerminalSession.swift

@@ -9,25 +9,21 @@ class TerminalSession: NSObject, ObservableObject, LocalProcessDelegate, Termina
     let id = UUID()
     let terminalView: TerminalView
     private var process: LocalProcess?
+    private let backgroundColor = NSColor.black
 
     @Published var title: String = "shell"
     @Published var isRunning: Bool = true
     @Published var currentDirectory: String?
 
-    init(fontSize: CGFloat) {
+    init(fontSize: CGFloat, theme: TerminalTheme) {
         terminalView = TerminalView(frame: NSRect(x: 0, y: 0, width: 600, height: 300))
         super.init()
 
         terminalView.terminalDelegate = self
 
-        // Solid black — matches every other element in the notch.
-        // The single `.opacity(notchOpacity)` on ContentView makes
-        // everything uniformly transparent.
-        terminalView.nativeBackgroundColor = .black
-        terminalView.nativeForegroundColor = .init(white: 0.9, alpha: 1.0)
-
         let font = NSFont.monospacedSystemFont(ofSize: fontSize, weight: .regular)
         terminalView.font = font
+        applyTheme(theme)
 
         startShell()
     }
@@ -64,6 +60,14 @@ class TerminalSession: NSObject, ObservableObject, LocalProcessDelegate, Termina
         terminalView.font = NSFont.monospacedSystemFont(ofSize: size, weight: .regular)
     }
 
+    func applyTheme(_ theme: TerminalTheme) {
+        // Keep the notch visually consistent while swapping the terminal's
+        // default foreground color and ANSI palette for command output.
+        terminalView.nativeBackgroundColor = backgroundColor
+        terminalView.nativeForegroundColor = theme.foregroundColor
+        terminalView.installColors(theme.ansiColors)
+    }
+
     func terminate() {
         process?.terminate()
         process = nil