chore: add license information and copyright notice to relevant files (#8)

Author: carmithersh

package.json

@@ -24,6 +24,7 @@
     "type": "git",
     "url": "git+https://github.com/jfrog/opencode-jfrog-plugin.git"
   },
+  "license": "Apache-2.0",
   "publishConfig": {
     "access": "public"
   },

src/index.test.ts

@@ -1,3 +1,4 @@
+// (c) JFrog Ltd. (2026)
 import { describe, it, expect, beforeEach, afterEach, mock } from 'bun:test';
 import { mkdirSync, writeFileSync, rmSync, mkdtempSync } from 'node:fs';
 import { tmpdir } from 'node:os';

src/index.ts

@@ -1,3 +1,4 @@
+// (c) JFrog Ltd. (2026)
 import type { Plugin } from '@opencode-ai/plugin';
 import {
   appendFileSync,