Add sample_start_step setting to configure when sampling starts (#949)

Co-authored-by: Jaret Burkett <jaretburkett@gmail.com>

ui/src/helpers/defaultSamples.ts

@@ -3,6 +3,7 @@ import { SampleConfig } from "@/types";
 export const defaultSampleConfig: SampleConfig = {
   sampler: 'flowmatch',
   sample_every: 250,
+  sample_start_step: 0,
   width: 1024,
   height: 1024,
   samples: [
@@ -52,6 +53,7 @@ export const defaultSampleConfig: SampleConfig = {
 export const defaultAudioSampleConfig: SampleConfig = {
   sampler: 'flowmatch',
   sample_every: 250,
+  sample_start_step: 0,
   width: 1024,
   height: 1024,
   samples: [
@@ -406,6 +408,7 @@ It's Converging!
 export const defaultIdeogramSamplesConfig: SampleConfig = {
   sampler: 'flowmatch',
   sample_every: 250,
+  sample_start_step: 0,
   width: 1024,
   height: 1024,
   samples: [
@@ -973,4 +976,4 @@ export const defaultIdeogramSamplesConfig: SampleConfig = {
   sample_steps: 30,
   num_frames: 1,
   fps: 1,
-}
+}