fix(full): replace abandoned azure-storage-blob with azure-oss/storage (#154)

Removes the abandoned `microsoft/azure-storage-blob` SDK from the
**full** image by adopting phpbu 6.0.32's migration to the maintained
`azure-oss/storage`.

## Background

`microsoft/azure-storage-blob` is abandoned upstream (Microsoft archived
it; Packagist `abandoned: true`, no replacement). It was a direct
require in the full image only because phpbu's Azure Blob sync adapter
was hardwired to it. That's now fixed at the root: phpbu migrated the
adapter to `azure-oss/storage` in
[sebastianfeldmann/phpbu#402](sebastianfeldmann/phpbu#402),
released in [phpbu
6.0.32](https://github.com/sebastianfeldmann/phpbu/releases/tag/6.0.32).

## What changed (`app/full/composer.json` + lock)

- `phpbu/phpbu` `^6.0` → `^6.0.32` (the release whose Azure adapter uses
azure-oss).
- Direct require `microsoft/azure-storage-blob: ^1.4` →
`azure-oss/storage: ^1.9` (phpbu lists azure-oss as
`suggest`/`require-dev`, so the full image still declares it explicitly
to enable the adapter).
- `composer update` removed `microsoft/azure-storage-blob` +
`microsoft/azure-storage-common` entirely; pulled `azure-oss/storage`
1.9.0, `azure-oss/storage-common`, `azure-oss/identity`.

## Verification

- `composer validate` clean; **no abandoned packages remain in the
lock**; `composer audit` reports no advisories.
- phpbu 6.0.32's `azureblob` sync runs in `--simulate` under PHP 8.5:
loads `AzureOss\Storage\Blob\BlobServiceClient` (no "SDK not loaded")
and masks the credential (`connectionString: ********`).
- The Security Scan (Trivy) runs on this PR and rebuilds the full image
— it should now be clean of the abandonment finding.

## Supersedes

This replaces the documentation-only workaround in #153 (which explained
why the abandoned package was kept). With the package removed, that note
is obsolete — closing #153 in favour of this fix.

Author: CybotTM

app/full/composer.json

@@ -15,10 +15,10 @@
     ],
     "require": {
         "php": ">=8.5",
-        "phpbu/phpbu": "^6.0",
+        "phpbu/phpbu": "^6.0.32",
         "aws/aws-sdk-php": "^3.10",
         "google/cloud-storage": "^2.0",
-        "microsoft/azure-storage-blob": "^1.4",
+        "azure-oss/storage": "^1.9",
         "phpseclib/phpseclib": "^3.0",
         "sebastianfeldmann/ftp": "^0.9.2",
         "kunalvarma05/dropbox-php-sdk": "^0.5",