refactor: [FC-0063] Block types processing refactoring

There is a problem that when we need to add a new block type processing,
we need to change the code in several places: update
`Cartridge.get_resource_content` to define the new processed content
type, add the OLX creation logic for this content type to OlxExport and
call it in OlxExport._create_olx_nodes.

It is decided to create a separate class responsible for a block type
processing. So, there are separate processors for HTML, LTI, QTI, Video
etc. The list of block type processors are specified in settings, so we
can control the processors to enable from settings. It will simlify a
processor disabling if, for example, a third-party xblock created by the
processor is not installed on the edX platform.

Technically, to implement a new content processor you need to create a
subclass of `cc2olx.content_processors.AbstractContentProcessor` and
implement its `process` method. The processors for content types
supported before are created.

MANIFEST.in

@@ -1,6 +1,7 @@
 include LICENSE
 include README.rst
 
+recursive-include src/cc2olx/templates *
 recursive-include requirements *
 recursive-include tests *
 recursive-exclude * __pycache__

pytest.ini

@@ -1,3 +1,3 @@
 [pytest]
 usefixtures = chdir_to_workspace
-DJANGO_SETTINGS_MODULE = cc2olx.django_settings
+DJANGO_SETTINGS_MODULE = cc2olx.settings

requirements/base.in

@@ -1,6 +1,8 @@
 # Core requirements for this package
+-c constraints.txt
 
 Django
+attrs
 lxml
 requests
 youtube-dl

requirements/base.txt

@@ -6,17 +6,19 @@
 #
 asgiref==3.8.1
     # via django
+attrs==25.1.0
+    # via -r requirements/base.in
 backports-zoneinfo==0.2.1
     # via django
-certifi==2024.12.14
+certifi==2025.1.31
     # via requests
 charset-normalizer==3.4.1
     # via requests
-django==4.2.17
+django==4.2.19
     # via -r requirements/base.in
 idna==3.10
     # via requests
-lxml==5.3.0
+lxml==5.3.1
     # via -r requirements/base.in
 requests==2.32.3
     # via -r requirements/base.in

requirements/ci.txt

@@ -6,142 +6,144 @@
 #
 asgiref==3.8.1
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   django
+attrs==25.1.0
+    # via -r requirements/quality.txt
 backports-zoneinfo==0.2.1
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   django
 black==24.8.0
-    # via -r /home/misha/work/cc2olx/requirements/quality.txt
-cachetools==5.5.0
+    # via -r requirements/quality.txt
+cachetools==5.5.1
     # via tox
-certifi==2024.12.14
+certifi==2025.1.31
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   requests
 chardet==5.2.0
     # via tox
 charset-normalizer==3.4.1
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   requests
 click==8.1.8
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   black
 colorama==0.4.6
     # via tox
 coverage[toml]==7.6.1
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   -r requirements/ci.in
     #   pytest-cov
 distlib==0.3.9
     # via virtualenv
-django==4.2.17
-    # via -r /home/misha/work/cc2olx/requirements/quality.txt
+django==4.2.19
+    # via -r requirements/quality.txt
 exceptiongroup==1.2.2
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   pytest
 filelock==3.16.1
     # via
     #   tox
     #   virtualenv
 flake8==7.1.1
-    # via -r /home/misha/work/cc2olx/requirements/quality.txt
+    # via -r requirements/quality.txt
 idna==3.10
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   requests
 iniconfig==2.0.0
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   pytest
-lxml==5.3.0
-    # via -r /home/misha/work/cc2olx/requirements/quality.txt
+lxml==5.3.1
+    # via -r requirements/quality.txt
 mccabe==0.7.0
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   flake8
 mypy-extensions==1.0.0
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   black
 packaging==24.2
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   black
     #   pyproject-api
     #   pytest
     #   tox
 pathspec==0.12.1
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   black
 platformdirs==4.3.6
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   black
     #   tox
     #   virtualenv
 pluggy==1.5.0
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   pytest
     #   tox
 pycodestyle==2.12.1
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   flake8
 pyflakes==3.2.0
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   flake8
 pyproject-api==1.8.0
     # via tox
 pytest==8.3.4
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   pytest-cov
     #   pytest-django
     #   pytest-mock
 pytest-cov==5.0.0
-    # via -r /home/misha/work/cc2olx/requirements/quality.txt
-pytest-django==4.9.0
-    # via -r /home/misha/work/cc2olx/requirements/quality.txt
+    # via -r requirements/quality.txt
+pytest-django==4.10.0
+    # via -r requirements/quality.txt
 pytest-mock==3.14.0
-    # via -r /home/misha/work/cc2olx/requirements/quality.txt
+    # via -r requirements/quality.txt
 requests==2.32.3
-    # via -r /home/misha/work/cc2olx/requirements/quality.txt
+    # via -r requirements/quality.txt
 sqlparse==0.5.3
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   django
 tomli==2.2.1
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   black
     #   coverage
     #   pyproject-api
     #   pytest
     #   tox
-tox==4.23.2
+tox==4.24.1
     # via -r requirements/ci.in
 typing-extensions==4.12.2
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   asgiref
     #   black
     #   tox
 urllib3==2.2.3
     # via
-    #   -r /home/misha/work/cc2olx/requirements/quality.txt
+    #   -r requirements/quality.txt
     #   requests
-virtualenv==20.28.1
+virtualenv==20.29.2
     # via tox
 xmlformatter==0.2.8
-    # via -r /home/misha/work/cc2olx/requirements/quality.txt
+    # via -r requirements/quality.txt
 youtube-dl==2021.12.17
-    # via -r /home/misha/work/cc2olx/requirements/quality.txt
+    # via -r requirements/quality.txt