Nextcloud 32/33 Compatibility: Remove deprecated API usage

This commit updates the SnappyMail integration app for Nextcloud to support version 32 and the upcoming version 33.

Key changes:
- Updated `info.xml` to allow `max-version="33"`.
- Refactored `AdminSettings`, `Application`, `FetchController`, `PageController`, `Settings` (command), and `InstallStep` to use Dependency Injection instead of the deprecated `\OC::$server` service container.
- Replaced deprecated `OC_User`, `OC_Util` (e.g. `addScript`), and `OC_App` calls with their `OCP` (public API) counterparts or modern equivalents.
- Updated `SnappyMailHelper` to use `\OCP\Server::get()` for static context access where DI is not possible.
- Moved script and style registration from Controllers (using deprecated `Util::addScript`) to templates using `script()` and `style()` helpers.
- Updated `Settings` console command to extend `Symfony\Component\Console\Command\Command` instead of deprecated `OC\Core\Command\Base`.
- Addressed PHP 8.4+ compatibility by adding explicit property types and nullable types where necessary in the integration code.

Co-authored-by: nextgen-networks <21206978+nextgen-networks@users.noreply.github.com>

.github/workflows/docker.yml

@@ -6,7 +6,9 @@ on:
     - 'v2.*'
 
 # This is needed to push to GitHub Container Registry. See https://docs.github.com/en/packages/working-with-a-github-packages-registry/working-with-the-container-registry
-permissions: write-all
+permissions:
+  contents: read
+  packages: write
 
 jobs:
   build:
@@ -24,7 +26,7 @@ jobs:
         DOCKER_METADATA_PR_HEAD_SHA: 'true'
       with:
         images: |
-          nextgen-networks/snappymail
+          djmaze/snappymail
           ghcr.io/${{ github.repository }}
         # type=ref,event=branch generates tag(s) on branch only. E.g. 'master', 'master-abc0123'
         # type=ref,event=tag generates tag(s) on tags only. E.g. 'v0.0.0', 'v0.0.0-abc0123', and 'latest'