In `@src/Migration/Destinations/Appwrite.php`:
- Around line 215-222: The call to Framework::STATIC() is invalid for Appwrite
v19.1.0 and will fatal; update the Sites creation in Appwrite.php by removing or
replacing Framework::STATIC() in the $this->sites->create(...) call inside the
Resource::TYPE_SITE block: either drop the framework argument if optional, or
map the incoming 'static' value to the correct Framework enum (e.g.,
Framework::REACTSTATIC or another valid Framework constant) before calling
$this->sites->create; update any other occurrences (e.g., the earlier match
handling that uses Framework::STATIC()) to perform the same mapping so the code
uses a valid Framework enum instead of Framework::STATIC().

In `@src/Migration/Transfer.php`:
- Around line 39-43: exportGroupSites currently only triggers exportSites() when
Resource::TYPE_SITE is requested, so requesting Resource::TYPE_SITE_VARIABLE
alone omits variables; update exportGroupSites() to also check for
Resource::TYPE_SITE_VARIABLE and either call exportSites() when variables are
requested or add a separate code path to export variables from exportSites()
output. Modify the conditional that tests for Resource::TYPE_SITE to include
Resource::TYPE_SITE_VARIABLE (or add an explicit branch handling
Resource::TYPE_SITE_VARIABLE) so site variables are exported even if TYPE_SITE
is not present, referencing the GROUP_SITES_RESOURCES constant and using
existing exportSites() logic to perform the actual extraction.

In `@src/Migration/Destinations/Appwrite.php`:
- Around line 1542-1635: The code uses Appwrite enums (Framework, Adapter,
BuildRuntime) that may not exist in the installed SDK and will throw fatal
errors; replace enum usage in the match blocks (the mappings that assign
$framework, $adapter, $buildRuntime from
$resource->getFramework()/getAdapter()/getBuildRuntime()) with plain string
values (or a validated string mapping) instead of Framework::*, Adapter::*,
BuildRuntime::* calls, or alternatively add a runtime guard (class_exists for
each enum) and fallback to the raw string when the enum class is missing; update
the match blocks in src/Migration/Destinations/Appwrite.php (the $framework,
$adapter, $buildRuntime assignments) to return strings (e.g., 'react', 'static',
'node-18.0') or use a safe mapping and remove direct enum references unless the
SDK dependency is constrained to a release that includes those enum classes.