feat: rebrand to website design, Apple HIG icons, ASCII onboarding animation

- Align Electron CSS with website design schema (Inter font, #FBFAF5/#191919
  palette, #213448/#94B4C1 accent)
- Generate proper app icons from logo.svg via cairosvg (no more Pillow ladder)
- Square bg icons for Electron/tray (Apple HIG — OS applies squircle mask)
- Circle bg icons for website favicon only
- Add scrolling ASCII agent-activity animation to onboarding hero left panel
- Remove dock.setIcon() — let macOS use bundle .icns with system mask
- Fix goal title overflow with min-w-0 for flex truncation

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/main/host-environment-service.ts

@@ -2,7 +2,7 @@ import { spawn } from "node:child_process";
 import { existsSync } from "node:fs";
 import { homedir } from "node:os";
 import { delimiter as pathDelimiter, join } from "node:path";
-import { app, nativeImage } from "electron";
+import { app } from "electron";
 
 interface HostEnvironmentDependencies {
   iconPath: string;
@@ -91,10 +91,7 @@ export async function prepareHostEnvironment({
     logger.info("[path] Skipping interactive shell PATH probe; using deterministic PATH setup only.");
   }
 
-  const appIcon = nativeImage.createFromPath(iconPath);
-  if (!appIcon.isEmpty()) {
-    if (process.platform === "darwin" && app.dock) {
-      app.dock.setIcon(appIcon);
-    }
-  }
+  // Dock icon: macOS uses the .icns from the app bundle with the system squircle
+  // mask applied automatically. Do not call dock.setIcon() — it bypasses the mask
+  // and renders the raw PNG oversized and square.
 }