refactor(ui): full rewrite instance and code struct (#129)

## Summary by Sourcery

Refactor the UI to modernize effect handling, routing, and legacy APIs
while adding a reusable alert dialog component and cleaning up obsolete
stores.

New Features:
- Introduce a shared SaturnEffect context via ParticleBackground so
pages can access the effect without relying on global window APIs.
- Add a Base UI–powered alert dialog component for consistent
confirmation and warning flows across the app.
- Define a central router configuration module with instance routes to
standardize page wiring.

Bug Fixes:
- Ensure SaturnEffect nullish checks are handled safely when forwarding
pointer and touch events from the home view.

Enhancements:
- Rewrite ParticleBackground to manage its own SaturnEffect lifecycle
via React state and context instead of global accessors.
- Update the home view to use the SaturnEffect hook, simplify
pointer/touch handlers, and remove legacy game and release store usage.
- Refine layout and accessibility attributes for various form field and
label components, including field grouping and error rendering keys.
- Simplify sidebar navigation and adjust the user dropdown trigger to
work with the updated dropdown menu API.
- Wrap the root outlet for the home route with ParticleBackground only
on the index path to limit the effect to the intended view.
- Clean up imports and code style in radio group and other UI primitives
for consistency.

Chores:
- Remove deprecated UI stores and utility modules that are no longer
used with the new architecture.
- Add changeset entries documenting the Saturn effect refactor,
ParticleBackground rewrite, and removal of legacy store code.

1 files changed, 113 insertions, 0 deletions

diff --git a/packages/ui/src/models/game.ts b/packages/ui/src/models/game.ts
new file mode 100644
index 0000000..5342078
--- /dev/null
+++ b/packages/ui/src/models/game.ts
@@ -0,0 +1,113 @@
+import { listen, type UnlistenFn } from "@tauri-apps/api/event";
+import { toast } from "sonner";
+import { create } from "zustand";
+import {
+  startGame as startGameCommand,
+  stopGame as stopGameCommand,
+} from "@/client";
+import type { GameExitedEvent } from "@/types/bindings/core";
+
+interface GameState {
+  runningInstanceId: string | null;
+  runningVersionId: string | null;
+  launchingInstanceId: string | null;
+  stoppingInstanceId: string | null;
+  lifecycleUnlisten: UnlistenFn | null;
+
+  isGameRunning: boolean;
+  startGame: (instanceId: string, versionId: string) => Promise<string | null>;
+  stopGame: (instanceId?: string | null) => Promise<string | null>;
+}
+
+export const useGameStore = create<GameState>((set, get) => ({
+  runningInstanceId: null,
+  runningVersionId: null,
+  launchingInstanceId: null,
+  stoppingInstanceId: null,
+  lifecycleUnlisten: null,
+
+  get isGameRunning() {
+    return get().runningInstanceId !== null;
+  },
+
+  startGame: async (instanceId, versionId) => {
+    const { isGameRunning, lifecycleUnlisten } = get();
+
+    if (isGameRunning) {
+      toast.info("A game is already running");
+      return null;
+    } else {
+      lifecycleUnlisten?.();
+    }
+
+    set({
+      launchingInstanceId: instanceId,
+    });
+    toast.info(`Preparing to launch ${versionId}...`);
+
+    const unlisten = await listen<GameExitedEvent>("game-exited", (event) => {
+      const { instanceId, versionId, wasStopped, exitCode } = event.payload;
+
+      set({
+        runningInstanceId: null,
+        runningVersionId: null,
+        launchingInstanceId: null,
+        stoppingInstanceId: null,
+      });
+
+      if (wasStopped) {
+        toast.success(
+          `Stopped Minecraft ${versionId} for instance ${instanceId}`,
+        );
+      } else {
+        toast.info(
+          `Minecraft ${versionId} exited with code ${exitCode} for instance ${instanceId}`,
+        );
+      }
+    });
+
+    set({ lifecycleUnlisten: unlisten });
+
+    try {
+      const message = await startGameCommand(instanceId, versionId);
+      set({
+        launchingInstanceId: null,
+        runningInstanceId: instanceId,
+        runningVersionId: versionId,
+      });
+      toast.success(message);
+      return message;
+    } catch (e) {
+      console.error(e);
+      set({ launchingInstanceId: null });
+      toast.error(`Error: ${e}`);
+      return null;
+    }
+  },
+
+  stopGame: async (instanceId) => {
+    const { runningInstanceId } = get();
+
+    if (!runningInstanceId) {
+      toast.info("No running game found");
+      return null;
+    }
+
+    if (instanceId !== runningInstanceId) {
+      toast.info("That instance is not the one currently running");
+      return null;
+    }
+
+    set({ stoppingInstanceId: runningInstanceId });
+
+    try {
+      return await stopGameCommand();
+    } catch (e) {
+      console.error("Failed to stop game:", e);
+      toast.error(`Failed to stop game: ${e}`);
+      return null;
+    } finally {
+      set({ stoppingInstanceId: null });
+    }
+  },
+}));