[REACTOS] Merge our bootcd and livecd into an all-in-one ReactOS BootCD (#7313)

CORE-9069, CORE-13525, RELEASE-11

This new BootCD contains the functionality of both the original bootcd
(text-mode 1st-stage installer) and the livecd (that will include the
1st-stage GUI installer later).
Our separate livecd ISOs become obsolete, and this completely removes
the need for the so-called "hybridcd" ISO.

Some details:

- The "hybridcd" build target is completely removed, since now the new
  BootCD *is* basically what we used to call "hybridcd".

- The "livecd" build target is kept so far (to minimize the code changes),
  but internally I start to refer to it as "LiveImage", and is reduced
  to a minimum.

  A minimal non-bootable "liveimg.iso" is built (but currently not
  included within the BootCD). Its purpose will be to implement the
  "ReactOS Live" functionality as a RAMDISK.
  (We currently don't support other file formats apart from ISO and
  flat disk for a RAMDISK).

  The "ReactOS Live" (non-RAMDISK) is implemented by adding to the
  BootCD file tree the files from the LiveImage.
  These files add two root directories, "Profiles" and "reactos"
  (which is the SystemRoot for the non-ramdisk LiveImage).

- The minimal text-mode ReactOS installation used for the 1st-stage
  installer, including USETUP itself, and the executable for the
  1st-stage GUI installer and the reactos.cab (installation source),
  are moved to the root directory called "i386" (ideally, one directory
  per architecture).

- The "bootcdregtest" target, i.e. the ISOs we feed our testbots with,
  are left untouched, i.e. they are only constituted of the 1st-stage
  text-mode installation only, but placed in a per-architecture root
  directory ("i386", etc. as for the bootcd).

- Remove the ACPI APIC/SMP entries from bootcd.ini. They will be made
  available via the Advanced Boot Options F8 menu in Debug builds, for
  testing purposes only, in a subsequent commit.

This commit is based upon an older SVN one:
svn path=/branches/setup_improvements/; revision=75273

.github/workflows/build.yml

@@ -70,7 +70,7 @@ jobs:
     - name: Build
       run: echo 'cmake --build ${{github.workspace}}/build -- -k0' | ${{github.workspace}}/RosBE-CI/RosBE.sh . 0 ${{matrix.arch}}
     - name: Generate ISOs
-      run: echo 'cmake --build ${{github.workspace}}/build --target bootcd --target livecd' | ${{github.workspace}}/RosBE-CI/RosBE.sh . 0 ${{matrix.arch}}
+      run: echo 'cmake --build ${{github.workspace}}/build --target bootcd' | ${{github.workspace}}/RosBE-CI/RosBE.sh . 0 ${{matrix.arch}}
     - name: Print ccache statistics
       run: ccache -s
     - name: Upload ISOs
@@ -79,7 +79,6 @@ jobs:
         name: reactos-${{matrix.compiler}}-${{matrix.arch}}-${{matrix.config}}-${{matrix.dllver}}-${{github.sha}}
         path: |
           build/bootcd.iso
-          build/livecd.iso
 
   build-msvc:
     strategy:
@@ -127,14 +126,13 @@ jobs:
     - name: Build
       run: cmake --build build -- -k0
     - name: Generate ISOs
-      run: cmake --build build --target bootcd --target livecd
+      run: cmake --build build --target bootcd
     - name: Upload ISOs
       uses: actions/upload-artifact@v5
       with:
         name: reactos-msvc${{matrix.toolset}}-${{matrix.arch}}-${{matrix.config}}-${{matrix.dllver}}-${{github.sha}}
         path: |
           build/bootcd.iso
-          build/livecd.iso
     - name: Upload debug symbols
       if: ${{ matrix.config == 'Debug' }}
       uses: actions/upload-artifact@v5
@@ -295,14 +293,13 @@ jobs:
     - name: Build
       run: cmake --build build -- -k0
     - name: Generate ISOs
-      run: cmake --build build --target bootcd --target livecd
+      run: cmake --build build --target bootcd
     - name: Upload ISOs
       uses: actions/upload-artifact@v5
       with:
         name: reactos-clang-cl-${{matrix.arch}}-${{matrix.config}}-${{github.sha}}
         path: |
           build/bootcd.iso
-          build/livecd.iso
     - name: Upload debug symbols
       if: ${{ matrix.config == 'Debug' }}
       uses: actions/upload-artifact@v5
@@ -334,4 +331,4 @@ jobs:
         cd build
         cmake -G "Visual Studio 17 2022" -A Win32 -DCMAKE_TOOLCHAIN_FILE:FILEPATH=toolchain-msvc.cmake -DARCH:STRING=i386 -DENABLE_ROSTESTS=1 -DENABLE_ROSAPPS=1 ${{github.workspace}}\src
     - name: Build
-      run: cmake --build ${{github.workspace}}\build --target bootcd --target livecd
+      run: cmake --build ${{github.workspace}}\build --target bootcd