Add some router docs

docs/index.md

@@ -33,6 +33,9 @@ features:
   - title: "@welshman/relay"
     details: In-memory relay and event store.
     link: "/relay"
+  - title: "@welshman/router"
+    details: Tools for relay selection.
+    link: "/router"
   - title: "@welshman/content"
     details: Parser and renderer for nostr notes with customizable formatting options.
     link: "/content"

docs/router/index.md

@@ -0,0 +1,48 @@
+# @welshman/router
+
+[![version](https://badgen.net/npm/v/@welshman/router)](https://npmjs.com/package/@welshman/router)
+
+Utilities for selecting nostr relays.
+
+## What's Included
+
+- **Router** - A configurable router class usable as a singleton which provides common relay selection scenarios.
+- **RouterScenario** - A scenario class which scores relays based on policy.
+- **getFilterSelections** - A high-level utility for inferring relay selections from fitlers.
+
+## Quick Example
+
+```typescript
+import {routerContext, addMaximalFallbacks, Router} from '@welshman/router'
+
+// Configure the global router instance based on RouterOptions
+Router.configure({
+  defaultRelays: ['wss://relay.example.com/'],
+  getPubkeyRelays: (pubkey, mode) => ['wss://myrelay.example.com/'],
+})
+
+// Get the singleton and use it to select some relays
+const router = Router.get()
+
+// Get a hint based on pubkey
+router.FromPubkeys(pubkeys).getUrl()
+
+// Send an event to the author's outbox and mentions' inboxes
+router.PublishEvent(event).getUrls()
+
+// Try as hard as we can to find a quoted note
+router
+  .FromPubkeys(event, quotedEventId, hints)
+  .allowLocal(true)
+  .allowOnion(true)
+  .allowInsecure(true)
+  .policy(addMaximalFallbacks)
+  .limit(10)
+  .getUrls()
+```
+
+## Installation
+
+```bash
+npm install @welshman/router
+```