Simple webchat for server (#1998)

* expose simple web interface on root domain

* embed index and add --path for choosing static dir

* allow server to multithread

because web browsers send a lot of garbage requests we want the server
to multithread when serving 404s for favicon's etc. To avoid blowing up
llama we just take a mutex when it's invoked.


* let's try this with the xxd tool instead and see if msvc is happier with that

* enable server in Makefiles

* add /completion.js file to make it easy to use the server from js

* slightly nicer css

* rework state management into session, expose historyTemplate to settings

---------

Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>

examples/server/deps.sh

@@ -0,0 +1,22 @@
+#!/bin/bash
+# Download and update deps for binary
+
+# get the directory of this script file
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+PUBLIC=$DIR/public
+OUTPUT=$DIR/templats.hpp
+
+echo "// Generated file, do not edit" > $OUTPUT
+echo "" > $OUTPUT
+
+echo "download js bundle files"
+curl https://npm.reversehttp.com/@preact/signals-core,@preact/signals,htm/preact,preact,preact/hooks > $PUBLIC/index.js
+echo >> $PUBLIC/index.js # add newline
+
+FILES=$(ls $PUBLIC)
+
+for FILE in $FILES; do
+  func=$(echo $FILE | tr '.' '_')
+  echo "generate $FILE.hpp ($func)"
+  xxd -n $func -i $PUBLIC/$FILE > $DIR/$FILE.hpp
+done