Import tests: test/encoding

Import the existing local project snapshot. This commit organizes existing files; it does not represent newly developed functionality.

test/encoding.js

@@ -0,0 +1,35 @@
+"use strict";
+
+const assert = require("node:assert/strict");
+const fs = require("node:fs");
+const path = require("node:path");
+
+const root = path.join(__dirname, "..");
+const files = [
+  "manifest.json",
+  "README.md",
+  "demo.html",
+  "src/content.js",
+  "popup/popup.html",
+  "popup/popup.js",
+  "test/content-engine.js",
+  "test/edge-cases.js"
+];
+const mojibakeMarkers = ["\u00D8\u00A7", "\u00D9\u0085", "\u00E2\u20AC", "\u00C3\u0097"];
+
+for (const file of files) {
+  const text = fs.readFileSync(path.join(root, file), "utf8");
+  for (const marker of mojibakeMarkers) {
+    assert.equal(text.includes(marker), false, `${file} contains a mojibake marker`);
+  }
+}
+
+const fixtures = fs.readFileSync(path.join(root, "test/content-engine.js"), "utf8");
+assert.match(fixtures, /[پچژگکی]/, "tests must contain real Persian-specific characters");
+
+const manifest = JSON.parse(fs.readFileSync(path.join(root, "manifest.json"), "utf8"));
+assert.match(manifest.name, /Persian/);
+assert.doesNotMatch(manifest.name, /Arabic/);
+assert.equal(manifest.content_scripts[0].match_origin_as_fallback, true);
+
+console.log("Encoding and manifest checks passed");