Fixes poor typing on get

Adds ensureFile

deno.json

@@ -1,6 +1,6 @@
 {
   "name": "@bearmetal/store",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "description": "A simple store for storing data in a JSON file.",
   "files": [
     "mod.ts",
@@ -9,6 +9,7 @@
   "exports": "./mod.ts",
   "imports": {
     "@std/assert": "jsr:@std/assert@^1.0.6",
+    "@std/fs": "jsr:@std/fs@^1.0.4",
     "@std/testing": "jsr:@std/testing@^1.0.3"
   }
 }

deno.lock

@@ -44,6 +44,7 @@
   "workspace": {
     "dependencies": [
       "jsr:@std/assert@^1.0.6",
+      "jsr:@std/fs@^1.0.4",
       "jsr:@std/testing@^1.0.3"
     ]
   }

store.ts

@@ -1,5 +1,9 @@
+import { ensureFileSync } from "@std/fs";
+
 const REFRESH_EVENT = "bm:refresh-store";
 
+type StoreValue = string | number | boolean;
+
 /**
  * A no-dep, lightweight, simple store for storing data in a JSON file.
  * usage:
@@ -37,6 +41,8 @@ export class BearMetalStore {
   constructor(storePath?: string) {
     this.storePath = storePath || Deno.env.get("BEAR_METAL_STORE_PATH") ||
       "./BearMetal/store.json";
+
+    ensureFileSync(this.storePath);
     this.EVENT_NAME = REFRESH_EVENT + this.storePath;
     this.readIn();
 
@@ -47,8 +53,8 @@ export class BearMetalStore {
    * @param key
    * @returns The value stored at the key, or undefined if the key doesn't exist.
    */
-  public get(key: string): string | number | boolean {
-    return this.store[key];
+  public get<T = StoreValue>(key: string): T {
+    return this.store[key] as T;
   }
 
   /**
@@ -56,7 +62,7 @@ export class BearMetalStore {
    * @param key
    * @param value
    */
-  public set(key: string, value: string | number | boolean): void {
+  public set(key: string, value: StoreValue): void {
     this.store[key] = value;
     this.writeOut();
   }