docs: add LICENSE, README, CHANGELOG, and license headers for npm publish

- Add combined MIT + Apache-2.0 LICENSE file (Copyright 2026 alk.dev)
- Add README.md with quick start for each adapter, lifecycle/close docs,
  operators, EventEnvelope, TypeScript, exports table, upstream attribution
- Add CHANGELOG.md with 0.1.0 entry
- Add SPDX license headers to original source files (WS client, WS server,
  Worker, index barrel)
- Update package.json: add author, repository, homepage, bugs; include
  CHANGELOG.md in files; update description

package.json

@@ -1,11 +1,20 @@
 {
   "name": "@alkdev/pubsub",
   "version": "0.1.0",
-  "description": "Type-safe publish/subscribe with pluggable event target adapters (in-process, Redis, WebSocket, Iroh)",
+  "description": "Type-safe publish/subscribe with pluggable event target adapters (in-process, Redis, WebSocket, Worker)",
   "type": "module",
   "main": "./dist/index.cjs",
   "module": "./dist/index.js",
   "types": "./dist/index.d.ts",
+  "author": "alk.dev",
+  "repository": {
+    "type": "git",
+    "url": "git+https://git.alk.dev/alkdev/pubsub.git"
+  },
+  "homepage": "https://git.alk.dev/alkdev/pubsub",
+  "bugs": {
+    "url": "https://git.alk.dev/alkdev/pubsub/issues"
+  },
   "exports": {
     ".": {
       "import": {
@@ -63,7 +72,8 @@
   },
   "sideEffects": false,
   "files": [
-    "dist"
+    "dist",
+    "CHANGELOG.md"
   ],
   "scripts": {
     "build": "tsup",