build: switch from yarn to npm to manage js dependencies and move js contents to root

yarn v1 is being deprecated and starts to have some issues

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

scripts/build/pictures.sh

@@ -0,0 +1,65 @@
+#!/bin/bash
+
+set -eu
+
+output_dir="../priv/static/img/pics"
+resolutions=(
+    480
+    1024
+    1920
+)
+ignore=(
+    homepage_background.png
+)
+
+file_extension () {
+    filename=$(basename -- "$file")
+    echo "${filename##*.}"
+}
+
+file_name () {
+    filename=$(basename -- "$file")
+    echo "${filename%.*}"
+}
+
+convert_image () {
+    name=$(file_name)
+    extension=$(file_extension)
+    res="$1w"
+    output="$output_dir/$name-$res.$extension"
+    convert -geometry "$resolution"x $file $output
+}
+
+
+progress() {
+    local w=80 p=$1;  shift
+    # create a string of spaces, then change them to dots
+    printf -v dots "%*s" "$(( $p*$w/100 ))" ""; dots=${dots// /.};
+    # print those dots on a fixed-width space plus the percentage etc. 
+    printf "\r\e[K|%-*s| %3d %% %s" "$w" "$dots" "$p" "$*"; 
+}
+
+
+echo "Generating responsive versions of the pictures…"
+
+if ! command -v convert &> /dev/null
+then
+    echo "$(tput setaf 1)ERROR: The convert command could not be found. You need to install ImageMagick.$(tput sgr 0)"
+    exit 1
+fi
+
+nb_files=$( shopt -s nullglob ; set -- $output_dir/* ; echo $#)
+
+tasks=$((${#resolutions[@]}*$nb_files))
+i=1
+for file in $output_dir/*
+do
+    if [[ -f $file ]]; then
+        for resolution in "${resolutions[@]}"; do
+            convert_image $resolution
+            progress $(($i*100/$tasks)) still working...
+            i=$((i+1))
+        done
+    fi
+done
+echo -e "\nDone!"