Introduce libexec folder in the distribution (#21427)

As of now, when installing scala and adding the `/bin` directory to
`PATH`, the `common`, `cli-common-platform` and `common-shared` scripts
are also added. This PR moves the following script to the `libexec`
folder to avoid the addition of the scripts.

Author: hamzaremmal

dist/bin-native-overrides/cli-common-platform

@@ -26,8 +26,8 @@ if [ -z "${PROG_HOME-}" ] ; then
   cd "$saveddir"
 fi
 
-source "$PROG_HOME/bin/common-shared"
-source "$PROG_HOME/bin/cli-common-platform"
+source "$PROG_HOME/libexec/common-shared"
+source "$PROG_HOME/libexec/cli-common-platform"
 
 SCALA_VERSION=""
 # iterate through lines in VERSION_SRC

dist/bin-native-overrides/cli-common-platform.bat

@@ -11,15 +11,15 @@ for %%f in ("%~dp0.") do (
     @rem get rid of the trailing slash
     set "_PROG_HOME=!_PROG_HOME:~0,-1!"
 )
-call "%_PROG_HOME%\bin\common.bat"
+call "%_PROG_HOME%\libexec\common.bat"
 if not %_EXITCODE%==0 goto end
 
 @rem #########################################################################
 @rem ## Main
 
 call :setScalaOpts
 
-call "%_PROG_HOME%\bin\cli-common-platform.bat"
+call "%_PROG_HOME%\libexec\cli-common-platform.bat"
 
 @rem SCALA_CLI_CMD_WIN is an array, set in cli-common-platform.bat.
 @rem WE NEED TO PASS '--skip-cli-updates' for JVM launchers but we actually don't need it for native launchers

dist/bin/scala

@@ -26,7 +26,7 @@ if [ -z "${PROG_HOME-}" ] ; then
   cd "$saveddir"
 fi
 
-source "$PROG_HOME/bin/common"
+source "$PROG_HOME/libexec/common"
 
 while [[ $# -gt 0 ]]; do
   case "$1" in

dist/bin/scala.bat

@@ -26,7 +26,7 @@ if [ -z "${PROG_HOME-}" ] ; then
   cd "$saveddir"
 fi
 
-source "$PROG_HOME/bin/common"
+source "$PROG_HOME/libexec/common"
 
 [ -z "$PROG_NAME" ] && PROG_NAME=$CompilerMain
 

dist/bin/scala_legacy

@@ -11,7 +11,7 @@ for %%f in ("%~dp0.") do (
     @rem get rid of the trailing slash
     set "_PROG_HOME=!_PROG_HOME:~0,-1!"
 )
-call "%_PROG_HOME%\bin\common.bat"
+call "%_PROG_HOME%\libexec\common.bat"
 if not %_EXITCODE%==0 goto end
 
 call :args %*

dist/bin/scalac

@@ -28,7 +28,7 @@ if [ -z "${PROG_HOME-}" ] ; then
   cd "$saveddir"
 fi
 
-source "$PROG_HOME/bin/common"
+source "$PROG_HOME/libexec/common"
 default_java_opts="-Xmx768m -Xms768m"
 withCompiler=true
 

dist/bin/scalac.bat

@@ -11,7 +11,7 @@ for %%f in ("%~dp0.") do (
     @rem get rid of the trailing slash
     set "_PROG_HOME=!_PROG_HOME:~0,-1!"
 )
-call "%_PROG_HOME%\bin\common.bat"
+call "%_PROG_HOME%\libexec\common.bat"
 if not %_EXITCODE%==0 goto end
 
 set _DEFAULT_JAVA_OPTS=-Xmx768m -Xms768m

dist/bin/scaladoc

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+SCALA_CLI_CMD_BASH=("\"$PROG_HOME/libexec/scala-cli\"")