docs(metamodel): reword origin.aggregate @filter description to be rendering-agnostic

The @filter attribute is a portable attr.filter object (the same declarative
predicate primitive layout.dataGrid uses), not SQL-specific — SQL FILTER (WHERE ...)
/ SQLite CASE WHEN is one codegen rendering (the projection view emitter), not the
attribute's meaning. Reword the registry/spec description to lead with the portable
predicate and treat SQL as an example target rendering. Description-only: no vocab,
behavior, or registration change; byte-identical across spec + embedded copies +
the C# inline schema. All 5 ports' registry-conformance green (0.15.19 shipped the
prior SQL-first wording; this lands in the next release).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FaRaYFjvWVV8D6h33ejj1m

Author: dmealing

fixtures/metamodel-docs/expected/types/origin.md

@@ -25,7 +25,7 @@ A count/sum/avg/min/max (@agg) computed over a column (@of) reached along a rela
 | Attribute | Type | Required | Default | Allowed values | Provider | Description |
 | --- | --- | --- | --- | --- | --- | --- |
 | `@agg` | string | yes |  | `count`, `sum`, `avg`, `min`, `max` | metaobjects-core-types | Aggregate function applied over the relationship path: count, sum, avg, min, or max. |
-| `@filter` | filter | no |  |  | metaobjects-core-types | Optional scoping filter restricting which related rows the aggregate spans, rendered as a SQL FILTER (WHERE ...) clause. Structured filter object desugared to canonical { field: { op: value } } form at parse time. |
+| `@filter` | filter | no |  |  | metaobjects-core-types | Optional structured predicate scoping which related rows the aggregate spans. A portable attr.filter object (eq/ne/in/isNull with and/or), desugared to canonical { field: { op: value } } at parse time; codegen renders it per target (e.g. SQL FILTER (WHERE ...) or SQLite CASE WHEN for a relational view). |
 | `@of` | string | yes |  |  | metaobjects-core-types | Dotted Entity.field reference identifying the column being aggregated (e.g. 'Week.durationMinutes'). |
 | `@via` | string | no |  |  | metaobjects-core-types | Dotted relationship path from the base entity to the aggregated rows (e.g. 'Program.weeks' or 'Program.weeks.workouts'). May be omitted only when exactly one single-hop relationship leads from the base entity to the @of entity (FR-024, ADR-0029). |
 

fixtures/registry-conformance/expected-registry.json

@@ -3096,7 +3096,7 @@
           "valueType": "filter",
           "isArray": false,
           "required": false,
-          "description": "Optional scoping filter restricting which related rows the aggregate spans, rendered as a SQL FILTER (WHERE ...) clause. Structured filter object desugared to canonical { field: { op: value } } form at parse time."
+          "description": "Optional structured predicate scoping which related rows the aggregate spans. A portable attr.filter object (eq/ne/in/isNull with and/or), desugared to canonical { field: { op: value } } at parse time; codegen renders it per target (e.g. SQL FILTER (WHERE ...) or SQLite CASE WHEN for a relational view)."
         },
         {
           "name": "of",

server/csharp/MetaObjects/Persistence/Origin/OriginConstants.cs

@@ -39,8 +39,9 @@ public static class OriginConstants
     public const string ORIGIN_AGGREGATE_ATTR_AGG = "agg";
     public const string ORIGIN_AGGREGATE_ATTR_OF  = "of";
     public const string ORIGIN_AGGREGATE_ATTR_VIA = "via";
-    // @filter (attr.filter object): optional scoping predicate on the aggregated
-    // rows, rendered as SQL FILTER (WHERE ...) by the projection view emitter.
+    // @filter (attr.filter object): an optional PORTABLE structured predicate scoping
+    // the aggregated rows (same shape as a preset filter). Codegen renders it per
+    // target -- the projection view emitter turns it into SQL FILTER (WHERE ...) / CASE WHEN.
     public const string ORIGIN_AGGREGATE_ATTR_FILTER = "filter";
 
     // collection attrs — a relationship-derived array of nested view-objects.

server/csharp/MetaObjects/Persistence/Origin/OriginSchema.cs

@@ -56,7 +56,7 @@ public static class OriginSchema
             Name: OriginConstants.ORIGIN_AGGREGATE_ATTR_FILTER,
             ValueType: AttrConstants.ATTR_SUBTYPE_FILTER,
             Required: false,
-            Description: "Optional scoping filter restricting which related rows the aggregate spans, rendered as a SQL FILTER (WHERE ...) clause. Structured filter object desugared to canonical { field: { op: value } } form at parse time."),
+            Description: "Optional structured predicate scoping which related rows the aggregate spans. A portable attr.filter object (eq/ne/in/isNull with and/or), desugared to canonical { field: { op: value } } at parse time; codegen renders it per target (e.g. SQL FILTER (WHERE ...) or SQLite CASE WHEN for a relational view)."),
     ];
 
     private static readonly IReadOnlyList<AttrSchema> CollectionOriginAttrs =

server/csharp/MetaObjects/SpecMetamodel/origin.json

@@ -27,7 +27,7 @@
         { "type": "attr", "subType": "string", "name": "agg", "min": 1, "max": 1, "allowedValues": ["count", "sum", "avg", "min", "max"], "description": "Aggregate function applied over the relationship path: count, sum, avg, min, or max." },
         { "type": "attr", "subType": "string", "name": "of", "min": 1, "max": 1, "description": "Dotted Entity.field reference identifying the column being aggregated (e.g. 'Week.durationMinutes')." },
         { "type": "attr", "subType": "string", "name": "via", "min": 0, "max": 1, "description": "Dotted relationship path from the base entity to the aggregated rows (e.g. 'Program.weeks' or 'Program.weeks.workouts'). May be omitted only when exactly one single-hop relationship leads from the base entity to the @of entity (FR-024, ADR-0029)." },
-        { "type": "attr", "subType": "filter", "name": "filter", "min": 0, "max": 1, "description": "Optional scoping filter restricting which related rows the aggregate spans, rendered as a SQL FILTER (WHERE ...) clause. Structured filter object desugared to canonical { field: { op: value } } form at parse time." }
+        { "type": "attr", "subType": "filter", "name": "filter", "min": 0, "max": 1, "description": "Optional structured predicate scoping which related rows the aggregate spans. A portable attr.filter object (eq/ne/in/isNull with and/or), desugared to canonical { field: { op: value } } at parse time; codegen renders it per target (e.g. SQL FILTER (WHERE ...) or SQLite CASE WHEN for a relational view)." }
       ]
     },
     {

server/java/metadata/src/main/java/com/metaobjects/origin/MetaOrigin.java

@@ -71,10 +71,11 @@ public abstract class MetaOrigin extends MetaData {
     public static final String ATTR_OF = "of";
 
     /**
-     * Optional scoping filter on {@code origin.aggregate} — a structured
-     * {@code attr.filter} object restricting which related rows the aggregate
-     * spans, rendered as SQL {@code FILTER (WHERE ...)} by the projection view
-     * emitter.
+     * Optional scoping filter on {@code origin.aggregate} — an optional PORTABLE
+     * structured {@code attr.filter} predicate scoping which related rows the
+     * aggregate spans (same shape as a preset filter). Codegen renders it per
+     * target — the projection view emitter turns it into SQL
+     * {@code FILTER (WHERE ...)} / SQLite {@code CASE WHEN}.
      */
     public static final String ATTR_FILTER = "filter";
 

server/python/src/metaobjects/meta/persistence/origin/origin_constants.py

@@ -22,6 +22,7 @@
 # aggregate attrs
 ORIGIN_ATTR_AGG = "agg"
 ORIGIN_ATTR_OF = "of"
-# @filter (attr.filter object): optional scoping predicate on the aggregated rows,
-# rendered as SQL FILTER (WHERE ...) by the projection view emitter.
+# @filter (attr.filter object): an optional PORTABLE structured predicate scoping the
+# aggregated rows (same shape as a preset filter). Codegen renders it per target -- the
+# projection view emitter turns it into SQL FILTER (WHERE ...) / SQLite CASE WHEN.
 ORIGIN_ATTR_FILTER = "filter"

server/python/src/metaobjects/spec_metamodel/origin.json

@@ -27,7 +27,7 @@
         { "type": "attr", "subType": "string", "name": "agg", "min": 1, "max": 1, "allowedValues": ["count", "sum", "avg", "min", "max"], "description": "Aggregate function applied over the relationship path: count, sum, avg, min, or max." },
         { "type": "attr", "subType": "string", "name": "of", "min": 1, "max": 1, "description": "Dotted Entity.field reference identifying the column being aggregated (e.g. 'Week.durationMinutes')." },
         { "type": "attr", "subType": "string", "name": "via", "min": 0, "max": 1, "description": "Dotted relationship path from the base entity to the aggregated rows (e.g. 'Program.weeks' or 'Program.weeks.workouts'). May be omitted only when exactly one single-hop relationship leads from the base entity to the @of entity (FR-024, ADR-0029)." },
-        { "type": "attr", "subType": "filter", "name": "filter", "min": 0, "max": 1, "description": "Optional scoping filter restricting which related rows the aggregate spans, rendered as a SQL FILTER (WHERE ...) clause. Structured filter object desugared to canonical { field: { op: value } } form at parse time." }
+        { "type": "attr", "subType": "filter", "name": "filter", "min": 0, "max": 1, "description": "Optional structured predicate scoping which related rows the aggregate spans. A portable attr.filter object (eq/ne/in/isNull with and/or), desugared to canonical { field: { op: value } } at parse time; codegen renders it per target (e.g. SQL FILTER (WHERE ...) or SQLite CASE WHEN for a relational view)." }
       ]
     },
     {

server/typescript/packages/metadata/src/persistence/origin/origin-constants.ts

@@ -40,9 +40,10 @@ export const ORIGIN_COLLECTION_ATTR_VIA = "via";
 export const ORIGIN_AGGREGATE_ATTR_AGG = "agg";
 export const ORIGIN_AGGREGATE_ATTR_OF  = "of";
 export const ORIGIN_AGGREGATE_ATTR_VIA = "via";
-// @filter (attr.filter object): optional scoping predicate restricting which
-// related rows the aggregate spans — rendered as SQL FILTER (WHERE …). Same
-// structured shape as a preset filter; consumed by the projection view emitter.
+// @filter (attr.filter object): an optional PORTABLE structured predicate scoping
+// which related rows the aggregate spans (same shape as a preset filter). Codegen
+// renders it per target — the projection view emitter turns it into SQL
+// FILTER (WHERE …) / SQLite CASE WHEN.
 export const ORIGIN_AGGREGATE_ATTR_FILTER = "filter";
 
 // aggregate function vocabulary

server/typescript/packages/metadata/src/persistence/origin/origin-definition.embedded.ts

@@ -90,7 +90,7 @@ export const ORIGIN_DEFINITION: ProviderDefinition = {
           "name": "filter",
           "min": 0,
           "max": 1,
-          "description": "Optional scoping filter restricting which related rows the aggregate spans, rendered as a SQL FILTER (WHERE ...) clause. Structured filter object desugared to canonical { field: { op: value } } form at parse time."
+          "description": "Optional structured predicate scoping which related rows the aggregate spans. A portable attr.filter object (eq/ne/in/isNull with and/or), desugared to canonical { field: { op: value } } at parse time; codegen renders it per target (e.g. SQL FILTER (WHERE ...) or SQLite CASE WHEN for a relational view)."
         }
       ]
     },