Document local networking prototype and protocol

Expand documentation to describe the current local networking prototype and its protocol. Adds a Current Architecture section and Fake Client responsibilities, clarifies that the Fallout 4 plugin currently only sends transforms (no receive loop yet), and documents implemented message types (welcome, transform, disconnect) with packet field descriptions and examples. Update player-sync and packets docs to reflect movementType, server/client timestamps, and the in-memory remote player state model used by server/fake_client.py. Flesh out server/README with run/test flow and implemented behavior. Revise dev-log with milestone entries, testing notes, and an entry template for future updates.

server/README.md

@@ -4,8 +4,13 @@ This folder is for the external multiplayer test server.
 
 The current server is a tiny local-only TCP test server. It listens on
 `127.0.0.1:7777`, accepts one or more clients, reads newline-separated JSON
-packets, prints received player transform packets, and broadcasts transform
-packets to every other connected client.
+packets, assigns incrementing `playerId` values, sends `welcome` packets, adds
+`playerId` and `serverTime` to transform packets, broadcasts transform packets
+to every other connected client, and broadcasts disconnect packets when clients
+disconnect.
+
+This is still a local prototype. It does not make Fallout 4 multiplayer
+playable yet.
 
 ## Run
 
@@ -14,14 +19,14 @@ cd server
 python server.py
 ```
 
-Then launch Fallout 4 through F4SE and move the player. The plugin should keep
-logging player position changes to `Fallout4Together.log`, and this server
-should print matching `transform` packets.
+Then launch Fallout 4 through F4SE and move the player. The plugin should send
+local player transform packets, and this server should print matching
+`transform` packets.
 
 If the server is not running, the plugin should log a warning and Fallout 4
 should continue launching normally.
 
-## Broadcast Test
+## Current Test Flow
 
 Terminal 1:
 
@@ -39,39 +44,51 @@ python fake_client.py
 
 Then launch Fallout 4 through F4SE and move the player.
 
-Expected result:
+Expected behavior:
 
 - The server assigns a `playerId` to each connected client and sends each client
   a `welcome` packet.
-- The fake client prints its `welcome` packet.
-- The server prints transform packets received from Fallout 4.
-- The server adds `playerId` and `serverTime` to each transform packet.
+- The server receives transforms from the Fallout 4 plugin.
+- The server adds `playerId` and `serverTime` to each transform packet before
+  broadcast.
 - The server broadcasts those transform packets to connected clients except the
   sender.
-- `fake_client.py` receives and prints the broadcast transform packets.
-- `fake_client.py` stores the latest remote player state for each `playerId`
-  in memory and prints a readable state summary after each transform update.
+- `fake_client.py` receives broadcast transform packets.
+- `fake_client.py` stores remote player state by `playerId`.
 - When a client disconnects, the server removes that client and broadcasts a
   `disconnect` packet with the departed `playerId` to the remaining clients.
 - `fake_client.py` removes disconnected players from its in-memory
-  `remote_players` table and prints the remaining tracked players.
+  `remote_players` table.
 
 The fake client exists so broadcast behavior can be tested before coordinating a
 second Fallout 4/F4SE instance. It stores remote player transform state only; it
 does not spawn remote actors or send movement.
 
-## Current Server Goals
+## Implemented
 
 - Start local server
 - Accept client connections
-- Receive transform packets
 - Assign server-owned player IDs
+- Send welcome packets
+- Receive transform packets
 - Add server timestamps
 - Broadcast transforms to other connected clients
-- Handle disconnects
+- Broadcast disconnect packets
+- Handle disconnect cleanup
 
-## Not Planned Yet
+## Working In Fake Client Only
 
+- Receiving welcome packets
+- Receiving transform broadcasts
+- Storing remote player state
+- Removing disconnected remote players
+
+The Fallout 4 plugin does not yet receive remote transforms from the server.
+
+## Planned Later
+
+- Fallout 4 plugin receive loop
+- Plugin-side remote player state storage
 - Remote actor spawning
 - Gameplay synchronization
 - Authentication