feat: add some mod api calls

- Get Project: Already existed but required a specific caller type. This
  is more general.
- Get Projects: A single call to multiple of the above

Both providers support these calls.

Signed-off-by: flow <flowlnlnln@gmail.com>

launcher/modplatform/flame/FlameAPI.h

@@ -3,8 +3,6 @@
 #include "modplatform/ModIndex.h"
 #include "modplatform/helpers/NetworkModAPI.h"
 
-#include "net/NetJob.h"
-
 class FlameAPI : public NetworkModAPI {
    public:
     auto matchFingerprints(const std::list<uint>& fingerprints, QByteArray* response) -> NetJob::Ptr;
@@ -12,6 +10,8 @@ class FlameAPI : public NetworkModAPI {
 
     auto getLatestVersion(VersionSearchArgs&& args) -> ModPlatform::IndexedVersion;
 
+    auto getProjects(QStringList addonIds, QByteArray* response) const -> NetJob::Ptr override;
+
    private:
     inline auto getSortFieldInt(QString sortString) const -> int
     {