fix: Schema compatibility - emoji → icon column rename

Production Outline DB uses 'icon' column instead of 'emoji' for documents
and revisions. Fixed all affected queries:

- documents.ts: SELECT queries
- advanced-search.ts: Search queries
- analytics.ts: Analytics + GROUP BY
- export-import.ts: Export/import metadata
- templates.ts: Template queries + INSERT
- collections.ts: Collection document listing
- revisions.ts: Revision comparison

reactions.emoji kept unchanged (correct schema)

Tested: 448 documents successfully queried from hub.descomplicar.pt

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/tools/collections.ts

@@ -583,7 +583,7 @@ export const collectionsTools: BaseTool<any>[] = [
             d.id,
             d."urlId",
             d.title,
-            d.emoji,
+            d.icon,
             d."collectionId",
             d."parentDocumentId",
             d.template,
@@ -1148,7 +1148,7 @@ export const collectionsTools: BaseTool<any>[] = [
           SELECT
             d.id,
             d.title,
-            d.emoji,
+            d.icon,
             d.text,
             d."createdAt",
             d."updatedAt",
@@ -1171,7 +1171,7 @@ export const collectionsTools: BaseTool<any>[] = [
         const exports = documentsResult.rows.map(doc => {
           const markdown = `---
 title: ${doc.title}
-emoji: ${doc.emoji || ''}
+icon: ${doc.icon || ''}
 author: ${doc.authorName}
 created: ${doc.createdAt}
 updated: ${doc.updatedAt}
@@ -1260,7 +1260,7 @@ ${doc.text || ''}
             SELECT
               d.id,
               d.title,
-              d.emoji,
+              d.icon,
               d.text,
               d."createdAt",
               d."updatedAt",
@@ -1282,7 +1282,7 @@ ${doc.text || ''}
           const documents = documentsResult.rows.map(doc => {
             const markdown = `---
 title: ${doc.title}
-emoji: ${doc.emoji || ''}
+icon: ${doc.icon || ''}
 author: ${doc.authorName}
 created: ${doc.createdAt}
 updated: ${doc.updatedAt}