feat: Add 22 new tools for complete Outline coverage (v1.1.0)

New modules (22 tools):
- Stars (3): list, create, delete - bookmarks
- Pins (3): list, create, delete - highlighted docs
- Views (2): list, create - view tracking
- Reactions (3): list, create, delete - emoji on comments
- API Keys (4): list, create, update, delete
- Webhooks (4): list, create, update, delete
- Backlinks (1): list - read-only view
- Search Queries (2): list, stats - analytics

Total tools: 86 -> 108 (+22)
All 22 new tools validated against Outline v0.78 schema.

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

src/tools/backlinks.ts

@@ -0,0 +1,99 @@
+/**
+ * MCP Outline PostgreSQL - Backlinks Tools
+ * Note: backlinks is a VIEW, not a table - read-only
+ * @author Descomplicar® | @link descomplicar.pt | @copyright 2026
+ */
+
+import { Pool } from 'pg';
+import { BaseTool, ToolResponse, PaginationArgs } from '../types/tools.js';
+import { validatePagination, isValidUUID } from '../utils/security.js';
+
+interface BacklinkListArgs extends PaginationArgs {
+  document_id?: string;
+  reverse_document_id?: string;
+}
+
+/**
+ * backlinks.list - List document backlinks
+ */
+const listBacklinks: BaseTool<BacklinkListArgs> = {
+  name: 'outline_backlinks_list',
+  description: 'List backlinks between documents. Shows which documents link to which. Backlinks is a view (read-only).',
+  inputSchema: {
+    type: 'object',
+    properties: {
+      document_id: {
+        type: 'string',
+        description: 'Filter by source document ID (UUID) - documents that link TO this',
+      },
+      reverse_document_id: {
+        type: 'string',
+        description: 'Filter by target document ID (UUID) - documents that ARE LINKED FROM this',
+      },
+      limit: {
+        type: 'number',
+        description: 'Maximum results (default: 25, max: 100)',
+      },
+      offset: {
+        type: 'number',
+        description: 'Results to skip (default: 0)',
+      },
+    },
+  },
+  handler: async (args, pgClient): Promise<ToolResponse> => {
+    const { limit, offset } = validatePagination(args.limit, args.offset);
+    const conditions: string[] = [];
+    const params: any[] = [];
+    let paramIndex = 1;
+
+    if (args.document_id) {
+      if (!isValidUUID(args.document_id)) throw new Error('Invalid document_id format');
+      conditions.push(`b."documentId" = $${paramIndex++}`);
+      params.push(args.document_id);
+    }
+
+    if (args.reverse_document_id) {
+      if (!isValidUUID(args.reverse_document_id)) throw new Error('Invalid reverse_document_id format');
+      conditions.push(`b."reverseDocumentId" = $${paramIndex++}`);
+      params.push(args.reverse_document_id);
+    }
+
+    const whereClause = conditions.length > 0 ? `WHERE ${conditions.join(' AND ')}` : '';
+
+    const result = await pgClient.query(
+      `
+      SELECT
+        b.id,
+        b."documentId",
+        b."reverseDocumentId",
+        b."userId",
+        b."createdAt",
+        b."updatedAt",
+        d.title as "documentTitle",
+        rd.title as "reverseDocumentTitle",
+        u.name as "userName"
+      FROM backlinks b
+      LEFT JOIN documents d ON b."documentId" = d.id
+      LEFT JOIN documents rd ON b."reverseDocumentId" = rd.id
+      LEFT JOIN users u ON b."userId" = u.id
+      ${whereClause}
+      ORDER BY b."createdAt" DESC
+      LIMIT $${paramIndex++} OFFSET $${paramIndex}
+      `,
+      [...params, limit, offset]
+    );
+
+    return {
+      content: [{
+        type: 'text',
+        text: JSON.stringify({
+          data: result.rows,
+          pagination: { limit, offset, total: result.rows.length },
+          note: 'Backlinks is a read-only view. Links are automatically detected from document content.',
+        }, null, 2),
+      }],
+    };
+  },
+};
+
+export const backlinksTools: BaseTool<any>[] = [listBacklinks];