feat: Initial confluence-mcp server for realtime collaboration

Provides 8 MCP tools for Confluence Cloud:
- confluence_list_spaces, confluence_create_space
- confluence_search, confluence_get_page
- confluence_create_page, confluence_update_page
- confluence_get_comments, confluence_add_comment

Uses Confluence REST API v2 with basic auth.
Registered in Claude Code and mcp-proxy.

Refs: CF-935

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

node_modules/jose/dist/webapi/lib/check_cek_length.js

@@ -0,0 +1,7 @@
+import { JWEInvalid } from '../util/errors.js';
+export function checkCekLength(cek, expected) {
+    const actual = cek.byteLength << 3;
+    if (actual !== expected) {
+        throw new JWEInvalid(`Invalid Content Encryption Key length. Expected ${expected} bits, got ${actual} bits`);
+    }
+}