chore: sync codebase remediation, gameplay systems, and docs

Security & infrastructure:
- Remove unused services/ (auth, spacetimedb) and auth.db
- Add .env.example template, expand .gitignore for env/db files
- Add GitHub Actions CI + commitlint config and workflows
- Add manual vendor chunking and source maps to docs/site vite configs

Shared UI & docs app:
- Add ARIA props and focus-visible rings to Button/Panel
- Add ButtonAsLink primitive; use shared Button in NotFound
- Wire @void-nav/ui into docs app; refresh content pages
- Replace Todo page with Kanban board

Gameplay (Bevy):
- Add ai module (behavior, faction, navigation, perception, spawning, states)
- Add narrative module (events, history, synthesis, ui)
- Refine galaxy contents and in-system flight/scene systems

apps/docs/src/components/NotFound.tsx

@@ -1,11 +1,11 @@
-import { Link } from "react-router-dom";
+import { ButtonAsLink } from "@void-nav/ui";
 
 export function NotFound() {
   return (
     <div className="mx-auto max-w-content">
       <h1>Page Not Found</h1>
       <p className="text-fg-dim">The requested route does not exist.</p>
-      <Link className="inline-flex items-center gap-2 rounded-lg border border-accent bg-accent px-4 py-2 text-[0.8rem] font-semibold text-bg transition-all duration-150 hover:bg-accent-hover" to="/docs">Back to documentation</Link>
+      <ButtonAsLink to="/docs" tone="primary">Back to documentation</ButtonAsLink>
     </div>
   );
 }