fix: emit declarations and lib via tsc (#76)

This changes from using esbuild to emit library code, and instead uses
typescript itself.

We don't currently ship type declarations since esbuild will not output
them.

package.json

@@ -33,7 +33,7 @@
     "pretest:node": "npm run build",
     "test:node": "mocha",
     "build": "npm run build:lib && npm run build:esm-bundle && npm run build:cjs-bundle",
-    "build:lib": "esbuild \"src/*.ts\" --outdir=lib --format=esm",
+    "build:lib": "tsc",
     "build:esm-bundle": "esbuild --bundle src/index.ts --outfile=loupe.js --format=esm",
     "build:cjs-bundle": "esbuild --bundle src/index.ts --outfile=loupe.js --format=cjs",
     "upload-coverage": "codecov"

tsconfig.json

@@ -8,8 +8,7 @@
     "isolatedModules": true,
     "useDefineForClassFields": true,
     "target": "es2018",
-    "noEmit": true,
-    "allowImportingTsExtensions": true,
+    "outDir": "./lib",
     "lib": ["es2022", "dom"],
     "strict": true,
     "declaration": true,