fix: port search and dimension safety guardrails

- enforce canonical dimensions across app and MCP surfaces
- prioritize title-first node search in UI and query tools
- add regression tests for ranking and dimension validation

app/api/dimensions/popular/route.ts

@@ -26,20 +26,13 @@ async function getPopularDimensionsSQLite() {
       SELECT nd.dimension, COUNT(*) AS count 
       FROM node_dimensions nd 
       GROUP BY nd.dimension
-    ),
-    all_dimensions AS (
-      SELECT DISTINCT dimension AS name FROM node_dimensions
-      UNION
-      SELECT name FROM dimensions
     )
-    SELECT ad.name AS dimension, 
+    SELECT d.name AS dimension, 
            COALESCE(dc.count, 0) AS count, 
-           dim.description
-    FROM all_dimensions ad
-    LEFT JOIN dimension_counts dc ON dc.dimension = ad.name
-    LEFT JOIN dimensions dim ON dim.name = ad.name
-    WHERE ad.name IS NOT NULL
-    ORDER BY LOWER(ad.name) ASC
+           d.description
+    FROM dimensions d
+    LEFT JOIN dimension_counts dc ON dc.dimension = d.name
+    ORDER BY LOWER(d.name) ASC
   `);
 
   return NextResponse.json({

app/api/nodes/[id]/route.ts

@@ -3,6 +3,7 @@ import { nodeService } from '@/services/database';
 import { autoEmbedQueue } from '@/services/embedding/autoEmbedQueue';
 import { hasSufficientContent } from '@/services/embedding/constants';
 import { normalizeDimensions, validateExplicitDescription } from '@/services/database/quality';
+import { formatUnknownDimensionsError, getUnknownDimensions } from '@/services/database/dimensionValidation';
 
 export const runtime = 'nodejs';
 
@@ -83,6 +84,13 @@ export async function PUT(
 
     if (Array.isArray(body.dimensions)) {
       updates.dimensions = normalizeDimensions(body.dimensions, 5);
+      const unknownDimensions = getUnknownDimensions(updates.dimensions as string[]);
+      if (unknownDimensions.length > 0) {
+        return NextResponse.json({
+          success: false,
+          error: formatUnknownDimensionsError(unknownDimensions)
+        }, { status: 400 });
+      }
     }
 
     delete updates.notes;

app/api/nodes/route.ts

@@ -5,6 +5,7 @@ import { autoEmbedQueue } from '@/services/embedding/autoEmbedQueue';
 import { generateDescription } from '@/services/database/descriptionService';
 import { scheduleAutoEdgeCreation } from '@/services/agents/autoEdge';
 import { normalizeDimensions, validateExplicitDescription } from '@/services/database/quality';
+import { formatUnknownDimensionsError, getUnknownDimensions } from '@/services/database/dimensionValidation';
 
 export const runtime = 'nodejs';
 
@@ -97,6 +98,13 @@ export async function POST(request: NextRequest) {
 
     // Process provided dimensions first (needed for description generation)
     const trimmedProvidedDimensions = normalizeDimensions(body.dimensions, 5);
+    const unknownDimensions = getUnknownDimensions(trimmedProvidedDimensions);
+    if (unknownDimensions.length > 0) {
+      return NextResponse.json({
+        success: false,
+        error: formatUnknownDimensionsError(unknownDimensions)
+      }, { status: 400 });
+    }
 
     // Use provided description if present, otherwise auto-generate
     const isUserSuppliedDescription = typeof body.description === 'string' && body.description.trim().length > 0;