Fix configs in docker builds (#14747)

<!-- First of all, THANK YOU for your contribution. -->

## Changes Proposed
- This fixes an issue where the .conf files aren't properly generated for the docker build
  - With this issue, the dbimport service in the docker compose file would fail to start due to insufficient config. 
  - related to PR #14707
- create a ".user" file extension for custom configs in `env/docker/etc/`
- Layers the ".dockerdist" file and the ".user" file over the ".dist" file (in that order), and then copies the ".dist" file to the base ".conf" file
- Docker specific config changes go in the ".dockerdist" file and should still be committed to the repo
- User specific config changes go in ".user" file and should not be committed to the repo
- If the ".dist" file and the base ".conf" file are different, the ".conf" will be backed up before the ".dist" file is copied into it

## Issues Addressed:
<!-- If your fix has a relating issue, link it below -->
- There isn't a specific issue, however this was reported and discussed in discord over the course of yesterday and today

## SOURCE:
<!-- If you can, include a source that can strengthen your claim -->

## Tests Performed:
<!-- Does it build without errors? Did you test in-game? What did you test? On which OS did you test? Describe any other tests performed -->
- Executing commands to build and start the game server
- after creating an account, I can log in and play without any issues. 


## How to Test the Changes:
<!-- Describe in a detailed step-by-step order how to test the changes -->

1.  Execute commands
   
    ```bash
    $ ./acore.sh docker clean:build && ./acore.sh docker build:nocache && ./acore.sh docker start:app
    ```
2. Create account and log in as normal

## Known Issues and TODO List:
<!-- Is there anything else left to do after this PR? -->

- The largest issue that comes to mind is this is a breaking change for docker users (though, so was the change that caused this)
  - Docker users (and nobody else, of course) can no longer use the ".conf" for custom changes in docker setups. 
  - Their custom changes will have to be migrated to the ".user" file
  - Since the old ".conf" file is backed up, users should have minimal trouble copying the changes in the old ".conf" file to the new ".user" file

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edit: link related PR

.gitignore

@@ -22,9 +22,7 @@
 !/env/docker/data/.gitkeep
 !/env/docker/etc/
 /env/docker/etc/*
-!/env/docker/etc/authserver.conf.dockerdist
-!/env/docker/etc/worldserver.conf.dockerdist
-!/env/docker/etc/dbimport.conf.dockerdist
+!/env/docker/etc/*.conf.dockerdist
 !/env/docker/logs/.gitkeep
 /.env*
 /apps/joiner

apps/compiler/includes/functions.sh

@@ -104,9 +104,7 @@ function comp_compile() {
 
   echo "Using $MTHREADS threads"
 
-  CWD=$(pwd)
-
-  cd $BUILDPATH
+  pushd "$BUILDPATH" >> /dev/null || exit 1
 
   comp_ccacheEnable
 
@@ -121,7 +119,7 @@ function comp_compile() {
     msys*)
       cmake --install . --config $CTYPE
 
-      cd $CWD
+      popd >> /dev/null || exit 1
 
       echo "Done"
       ;;
@@ -138,7 +136,7 @@ function comp_compile() {
       echo "Cmake install..."
       sudo cmake --install . --config $CTYPE
 
-      cd $CWD
+      popd >> /dev/null || exit 1
 
       # set all aplications SUID bit
       echo "Setting permissions on binary files"
@@ -149,13 +147,16 @@ function comp_compile() {
 
       if [[ $DOCKER = 1 && $DISABLE_DOCKER_CONF != 1 ]]; then
         echo "Generating confs..."
-        cp -n "$DOCKER_ETC_FOLDER/worldserver.conf.dockerdist" "${confDir}/worldserver.conf"
-        cp -n "$DOCKER_ETC_FOLDER/authserver.conf.dockerdist" "${confDir}/authserver.conf"
-        cp -n "$DOCKER_ETC_FOLDER/dbimport.conf.dockerdist" "${confDir}/dbimport.conf"
+        for dockerdist in "$DOCKER_ETC_FOLDER"/*.dockerdist; do
+          base_conf="$(echo "$dockerdist" | rev | cut -f1 -d. --complement | rev)"
+          cp -nv "$base_conf.dist" "$base_conf"
+          # Move configs from .conf.dockerdist to .conf
+          conf_layer "$dockerdist" "$base_conf" " # Copied from dockerdist"
+        done
       fi
 
       echo "Done"
-    ;;
+      ;;
   esac
 
   runHooks "ON_AFTER_BUILD"
@@ -170,3 +171,31 @@ function comp_all() {
   comp_clean
   comp_build
 }
+
+# conf_layer FILENAME FILENAME
+# Layer the configuration parameters from the first argument onto the second argument
+function conf_layer() {
+  LAYER="$1"
+  BASE="$2"
+  COMMENT="$3"
+
+  grep -E "^[a-zA-Z\.0-9]+\s*=.*$" "$LAYER" \
+    | while read -r param
+      do
+        NOSPACE="$(tr -d '[:space:]' <<< "$param")"
+        KEY="$(cut -f1 -d= <<< "$NOSPACE")"
+        VAL="$(cut -f2 -d= <<< "$NOSPACE")"
+        # if key not in base or val not in line
+        if grep -qE "^$KEY" "$BASE" && ! grep -qE "^$KEY.*=.*$VAL" "$BASE"; then
+          # Replace line
+          # Prevent issues with shell quoting 
+          sed -i \
+            's,^'"$KEY"'.*,'"$KEY = $VAL$COMMENT"',g' \
+            "$BASE"
+        else
+          # insert line
+          echo "$KEY = $VAL$COMMENT" >> "$BASE"
+        fi
+      done
+  echo "Layered $LAYER onto $BASE"
+}