chore(spec): regenerate references, authorable surface and liveness counts for nullLabel

Claude-Session: https://claude.ai/code/session_01Fd2ukZvGZZbccf6CSDPzuv
Co-Authored-By: Claude <noreply@anthropic.com>

Author: claude

content/docs/references/ui/dataset.mdx

@@ -75,6 +75,7 @@ const result = DatasetSchema.parse(data);
 | **field** | `string` | ✅ | Base field, or `relationship[.relationship].field` path. A column reference, never a SQL expression. |
 | **type** | `Enum<'string' \| 'number' \| 'date' \| 'boolean' \| 'lookup'>` | optional |  |
 | **dateGranularity** | `Enum<'day' \| 'week' \| 'month' \| 'quarter' \| 'year'>` | optional |  |
+| **nullLabel** | `string \| Record<string, string>` | optional | Label for the bucket of rows whose value for this dimension is null (e.g. "System" on a user axis). Display copy only: grouping is unchanged. When absent, consumers fall back to their own default label for that bucket. |
 
 ### Nested Shape: `Dataset.measures[number]`
 
@@ -111,6 +112,7 @@ const result = DatasetSchema.parse(data);
 | **field** | `string` | ✅ | Base field, or `relationship[.relationship].field` path. A column reference, never a SQL expression. |
 | **type** | `Enum<'string' \| 'number' \| 'date' \| 'boolean' \| 'lookup'>` | optional |  |
 | **dateGranularity** | `Enum<'day' \| 'week' \| 'month' \| 'quarter' \| 'year'>` | optional |  |
+| **nullLabel** | `string \| Record<string, string>` | optional | Label for the bucket of rows whose value for this dimension is null (e.g. "System" on a user axis). Display copy only: grouping is unchanged. When absent, consumers fall back to their own default label for that bucket. |
 
 
 ---

packages/spec/authorable-surface/ui.json

@@ -411,6 +411,7 @@
     "ui/DatasetDimension:field",
     "ui/DatasetDimension:label",
     "ui/DatasetDimension:name",
+    "ui/DatasetDimension:nullLabel",
     "ui/DatasetDimension:type",
     "ui/DatasetMeasure:aggregate",
     "ui/DatasetMeasure:currency",

packages/spec/liveness/state-counts/dataset.md

@@ -12,4 +12,4 @@ committed anywhere: `check:liveness` sums the shards when it reads them.
 
 | Type | live | exp | elsewhere | dead | planned | classified |
 |---|---|---|---|---|---|---|
-| `dataset` | 27 | 0 | 0 | 0 | 0 | 27 |
+| `dataset` | 27 | 0 | 0 | 0 | 1 | 28 |