Added ability to set the caption extention in dataset viewer, captioner, and trainer so one dataset can have multiple caption styles in different files with different extensions. Added dataset caption template for a blank ideogram 4 formatted template.

ui/src/components/CaptionSimpleJob.tsx

@@ -121,6 +121,20 @@ const CaptionSimpleJob: React.FC<Props> = ({ jobConfig, setJobConfig, gpuIDs, se
             }}
             options={quantizationOptions}
           />
+          <div className="mt-4">
+            <CreatableSelectInput
+              label="Caption Extension"
+              value={jobConfig.config.process[0].caption.caption_extension || 'txt'}
+              onChange={value => {
+                setJobConfig(value, 'config.process[0].caption.caption_extension');
+              }}
+              options={[
+                { value: 'txt', label: 'txt' },
+                { value: 'json', label: 'json' },
+                { value: 'caption', label: 'caption' },
+              ]}
+            />
+          </div>
           {additionalSections.includes('caption.max_res') && (
             <div className="mt-4">
               <SelectInput