feat(DT-3887): remove Dispatch Rate Epsilon from compute scaling UI (#3334)

Removes the scaleUpDispatchRateEpsilon input field from the serverless
worker compute scaling configuration UI per feedback from Muneeb Ahmad.

This is a UI-only removal. The service layer API mapping remains intact
so the backend contract is unchanged and existing deployments are not
affected.

Files changed:
- compute-fields.svelte: remove Input block + Props entries + destructure
- shared.ts: remove field from Zod scalingFields schema
- serverless-worker-create-form.svelte: remove initial data + bind prop
- create-version-form.svelte: remove initial data + bind prop
- edit-version-form.svelte: remove Props interface + initial data + bind
- serverless-worker-create.svelte: remove from buildLambdaComputeConfig
- worker-deployment-version-create.svelte: same
- worker-deployment-version-edit.svelte: same (2 references)
- version-compute-details.svelte: remove read-only display row
- en/workers.ts: remove label and hint i18n keys
- en/deployments.ts: remove dispatch-rate-epsilon i18n key

Author: rossnelson

src/lib/components/deployments/version-compute-details.svelte

@@ -17,7 +17,6 @@
     scalerParams.scaleUpCooloffMs !== undefined ||
       scalerParams.scaleUpBacklogThreshold !== undefined ||
       scalerParams.maxWorkerLifetimeMs !== undefined ||
-      scalerParams.scaleUpDispatchRateEpsilon !== undefined ||
       scalerParams.metricsPollIntervalMs !== undefined,
   );
 </script>
@@ -90,16 +89,6 @@
             >
           </div>
         {/if}
-        {#if scalerParams.scaleUpDispatchRateEpsilon !== undefined}
-          <div class="flex gap-1">
-            <span class="font-medium text-secondary"
-              >{translate('deployments.dispatch-rate-epsilon')}</span
-            >
-            <span class="text-primary"
-              >{scalerParams.scaleUpDispatchRateEpsilon}</span
-            >
-          </div>
-        {/if}
         {#if scalerParams.metricsPollIntervalMs !== undefined}
           <div class="flex gap-1">
             <span class="font-medium text-secondary"

src/lib/components/workers/serverless-worker-form/compute-fields.svelte

@@ -10,7 +10,6 @@
     scaleUpCooloffMs?: number;
     scaleUpBacklogThreshold?: number;
     maxWorkerLifetimeMs?: number;
-    scaleUpDispatchRateEpsilon?: number;
     metricsPollIntervalMs?: number;
     errors?: {
       lambdaArn?: string[];
@@ -19,7 +18,6 @@
       scaleUpCooloffMs?: string[];
       scaleUpBacklogThreshold?: string[];
       maxWorkerLifetimeMs?: string[];
-      scaleUpDispatchRateEpsilon?: string[];
       metricsPollIntervalMs?: string[];
     };
   }
@@ -31,7 +29,6 @@
     scaleUpCooloffMs = $bindable(),
     scaleUpBacklogThreshold = $bindable(),
     maxWorkerLifetimeMs = $bindable(),
-    scaleUpDispatchRateEpsilon = $bindable(),
     metricsPollIntervalMs = $bindable(),
     errors = {},
   }: Props = $props();
@@ -135,22 +132,6 @@
       error={!!errors.maxWorkerLifetimeMs?.[0]}
       placeholder="600000"
     />
-    <Input
-      value={scaleUpDispatchRateEpsilon !== undefined
-        ? String(scaleUpDispatchRateEpsilon)
-        : ''}
-      onchange={(e) => {
-        const val = (e.target as HTMLInputElement).value;
-        scaleUpDispatchRateEpsilon = val === '' ? undefined : Number(val);
-      }}
-      id="scaleUpDispatchRateEpsilon"
-      name="scaleUpDispatchRateEpsilon"
-      label={translate('workers.scale-up-dispatch-rate-epsilon-label')}
-      hintText={errors.scaleUpDispatchRateEpsilon?.[0] ||
-        translate('workers.scale-up-dispatch-rate-epsilon-hint')}
-      error={!!errors.scaleUpDispatchRateEpsilon?.[0]}
-      placeholder="0"
-    />
     <Input
       value={metricsPollIntervalMs !== undefined
         ? String(metricsPollIntervalMs)

src/lib/components/workers/serverless-worker-form/create-version-form.svelte

@@ -32,7 +32,6 @@
       scaleUpCooloffMs: undefined as number | undefined,
       scaleUpBacklogThreshold: undefined as number | undefined,
       maxWorkerLifetimeMs: undefined as number | undefined,
-      scaleUpDispatchRateEpsilon: undefined as number | undefined,
       metricsPollIntervalMs: undefined as number | undefined,
     },
     {
@@ -92,7 +91,6 @@
           bind:scaleUpCooloffMs={$form.scaleUpCooloffMs}
           bind:scaleUpBacklogThreshold={$form.scaleUpBacklogThreshold}
           bind:maxWorkerLifetimeMs={$form.maxWorkerLifetimeMs}
-          bind:scaleUpDispatchRateEpsilon={$form.scaleUpDispatchRateEpsilon}
           bind:metricsPollIntervalMs={$form.metricsPollIntervalMs}
           errors={$errors}
         />

src/lib/components/workers/serverless-worker-form/edit-version-form.svelte

@@ -20,7 +20,6 @@
       scaleUpCooloffMs?: number;
       scaleUpBacklogThreshold?: number;
       maxWorkerLifetimeMs?: number;
-      scaleUpDispatchRateEpsilon?: number;
       metricsPollIntervalMs?: number;
     };
     onSubmit: (data: EditVersionFormData) => Promise<void>;
@@ -41,7 +40,6 @@
       scaleUpCooloffMs: initialData.scaleUpCooloffMs,
       scaleUpBacklogThreshold: initialData.scaleUpBacklogThreshold,
       maxWorkerLifetimeMs: initialData.maxWorkerLifetimeMs,
-      scaleUpDispatchRateEpsilon: initialData.scaleUpDispatchRateEpsilon,
       metricsPollIntervalMs: initialData.metricsPollIntervalMs,
     },
     {
@@ -81,7 +79,6 @@
           bind:scaleUpCooloffMs={$form.scaleUpCooloffMs}
           bind:scaleUpBacklogThreshold={$form.scaleUpBacklogThreshold}
           bind:maxWorkerLifetimeMs={$form.maxWorkerLifetimeMs}
-          bind:scaleUpDispatchRateEpsilon={$form.scaleUpDispatchRateEpsilon}
           bind:metricsPollIntervalMs={$form.metricsPollIntervalMs}
           errors={$errors}
         />

src/lib/components/workers/serverless-worker-form/serverless-worker-create-form.svelte

@@ -51,7 +51,6 @@
     scaleUpCooloffMs: undefined as number | undefined,
     scaleUpBacklogThreshold: undefined as number | undefined,
     maxWorkerLifetimeMs: undefined as number | undefined,
-    scaleUpDispatchRateEpsilon: undefined as number | undefined,
     metricsPollIntervalMs: undefined as number | undefined,
   };
 
@@ -134,7 +133,6 @@
             bind:scaleUpCooloffMs={$form.scaleUpCooloffMs}
             bind:scaleUpBacklogThreshold={$form.scaleUpBacklogThreshold}
             bind:maxWorkerLifetimeMs={$form.maxWorkerLifetimeMs}
-            bind:scaleUpDispatchRateEpsilon={$form.scaleUpDispatchRateEpsilon}
             bind:metricsPollIntervalMs={$form.metricsPollIntervalMs}
             errors={$errors}
           />

src/lib/components/workers/serverless-worker-form/shared.ts

@@ -19,7 +19,6 @@ const scalingFields = {
   scaleUpCooloffMs: z.number().int().min(0).optional(),
   scaleUpBacklogThreshold: z.number().int().min(0).optional(),
   maxWorkerLifetimeMs: z.number().int().min(0).optional(),
-  scaleUpDispatchRateEpsilon: z.number().min(0).optional(),
   metricsPollIntervalMs: z.number().int().min(10000).optional(),
 };
 

src/lib/i18n/locales/en/deployments.ts

@@ -71,7 +71,6 @@ export const Strings = {
   'scale-up-cooloff': 'Scale-up Cooloff',
   'backlog-threshold': 'Backlog Threshold',
   'max-worker-lifetime': 'Max Worker Lifetime',
-  'dispatch-rate-epsilon': 'Dispatch Rate Epsilon',
   'metrics-poll-interval': 'Metrics Poll Interval',
   'filter-deployments': 'Filter deployments',
   'drainage-status': 'Drainage Status',

src/lib/i18n/locales/en/workers.ts

@@ -281,9 +281,6 @@ export const Strings = {
   'max-worker-lifetime-ms-label': 'Max Worker Lifetime (ms)',
   'max-worker-lifetime-ms-hint':
     'Refresh a worker after this many ms when there is backlog. 0 = disabled. Default: 600000.',
-  'scale-up-dispatch-rate-epsilon-label': 'Dispatch Rate Epsilon',
-  'scale-up-dispatch-rate-epsilon-hint':
-    'Suppress scale-up when processing rate change is within this value. 0 = disabled.',
   'metrics-poll-interval-ms-label': 'Metrics Poll Interval (ms)',
   'metrics-poll-interval-ms-hint':
     'Interval between metrics polls. Min: 10000. Default: 60000.',

src/lib/pages/serverless-worker-create.svelte

@@ -80,7 +80,6 @@
         scaleUpCooloffMs: data.scaleUpCooloffMs,
         scaleUpBacklogThreshold: data.scaleUpBacklogThreshold,
         maxWorkerLifetimeMs: data.maxWorkerLifetimeMs,
-        scaleUpDispatchRateEpsilon: data.scaleUpDispatchRateEpsilon,
         metricsPollIntervalMs: data.metricsPollIntervalMs,
       },
     );

src/lib/pages/worker-deployment-version-create.svelte

@@ -45,7 +45,6 @@
           scaleUpCooloffMs: data.scaleUpCooloffMs,
           scaleUpBacklogThreshold: data.scaleUpBacklogThreshold,
           maxWorkerLifetimeMs: data.maxWorkerLifetimeMs,
-          scaleUpDispatchRateEpsilon: data.scaleUpDispatchRateEpsilon,
           metricsPollIntervalMs: data.metricsPollIntervalMs,
         },
       );