feat(server): implement vid_gen async API and mode-aware capabilities (#1437)

src/stable-diffusion.cpp

@@ -2390,6 +2390,14 @@ struct sd_ctx_t {
     StableDiffusionGGML* sd = nullptr;
 };
 
+static bool sd_version_supports_video_generation(SDVersion version) {
+    return version == VERSION_SVD || sd_version_is_wan(version);
+}
+
+static bool sd_version_supports_image_generation(SDVersion version) {
+    return !sd_version_supports_video_generation(version);
+}
+
 sd_ctx_t* new_sd_ctx(const sd_ctx_params_t* sd_ctx_params) {
     sd_ctx_t* sd_ctx = (sd_ctx_t*)malloc(sizeof(sd_ctx_t));
     if (sd_ctx == nullptr) {
@@ -2419,6 +2427,20 @@ void free_sd_ctx(sd_ctx_t* sd_ctx) {
     free(sd_ctx);
 }
 
+SD_API bool sd_ctx_supports_image_generation(const sd_ctx_t* sd_ctx) {
+    if (sd_ctx == nullptr || sd_ctx->sd == nullptr) {
+        return false;
+    }
+    return sd_version_supports_image_generation(sd_ctx->sd->version);
+}
+
+SD_API bool sd_ctx_supports_video_generation(const sd_ctx_t* sd_ctx) {
+    if (sd_ctx == nullptr || sd_ctx->sd == nullptr) {
+        return false;
+    }
+    return sd_version_supports_video_generation(sd_ctx->sd->version);
+}
+
 enum sample_method_t sd_get_default_sample_method(const sd_ctx_t* sd_ctx) {
     if (sd_ctx != nullptr && sd_ctx->sd != nullptr) {
         if (sd_version_is_dit(sd_ctx->sd->version)) {