docs: update README with IRC-inspired unified API design

- Document simplified endpoint structure
- Single message stream (GET /messages) for all message types
- Unified send (POST /messages) with 'to' field
- GET /state replaces separate /me and /channels
- GET /history for scrollback
- Update project status

README.md

@@ -87,48 +87,57 @@ Fields:
 
 ### API Endpoints
 
-All endpoints accept and return `application/json`.
+All endpoints accept and return `application/json`. Authenticated endpoints
+require `Authorization: Bearer <token>` header.
 
-#### Authentication
+The API follows an IRC-inspired design: one unified message stream for all
+message types (channel messages, DMs, server notices), with a simple `to` field
+for addressing.
+
+#### Registration
 
 ```
-POST /api/v1/register      — Create account (nick, password) → token
-POST /api/v1/login          — Authenticate → token
-POST /api/v1/logout         — Invalidate token
+POST /api/v1/register       — Create account { "nick": "..." } → { id, nick, token }
 ```
 
-#### Session & Messages
+#### State
 
 ```
-GET  /api/v1/messages       — Retrieve queued messages (long-poll supported)
-                               Query params: ?after=<message-id>&timeout=30
-POST /api/v1/messages       — Send a message or command
-GET  /api/v1/history        — Retrieve channel/DM history
-                               Query params: ?target=#channel&before=<id>&limit=50
+GET  /api/v1/state           — User state: nick, id, and list of joined channels
+                                Replaces separate /me and /channels endpoints
+```
+
+#### Messages (unified stream)
+
+```
+GET  /api/v1/messages        — Single message stream (long-poll supported)
+                                All message types: channel, DM, notices, events
+                                Query params: ?after=<message-id>&timeout=30
+POST /api/v1/messages        — Send a message
+                                Body: { "to": "#channel" or "nick", "content": "..." }
+```
+
+#### History
+
+```
+GET  /api/v1/history         — Fetch history for a target (channel or DM)
+                                Query params: ?target=#channel&before=<id>&limit=50
+                                For DMs: ?target=nick&before=<id>&limit=50
 ```
 
 #### Channels
 
 ```
-GET  /api/v1/channels                — List joined channels
-POST /api/v1/channels/join           — Join a channel
-POST /api/v1/channels/part           — Leave a channel
-GET  /api/v1/channels/{name}         — Channel info (topic, members, modes)
-POST /api/v1/channels/{name}/topic   — Set channel topic
-```
-
-#### Users
-
-```
-GET  /api/v1/users/me        — Current user info
-POST /api/v1/users/nick      — Change nick
-GET  /api/v1/users/{nick}    — User info (online status, idle time)
+GET  /api/v1/channels/all              — List all server channels
+POST /api/v1/channels/join             — Join a channel { "channel": "#name" }
+DELETE /api/v1/channels/{name}         — Part (leave) a channel
+GET  /api/v1/channels/{name}/members   — Channel member list
 ```
 
 #### Server Info
 
 ```
-GET  /api/v1/server          — Server info (name, version, MOTD, user count)
+GET  /api/v1/server          — Server info (name, MOTD)
 GET  /.well-known/healthcheck.json  — Health check
 ```
 
@@ -265,7 +274,8 @@ Per gohttpserver conventions:
 
 ## Status
 
-**Design phase.** This README is the spec. Implementation has not started.
+**Implementation in progress.** Core API is functional with SQLite storage and
+embedded web client.
 
 ## License