fix(emergency): drastically lower high-volume mode activation thresholds

EMERGENCY FIX for bluesky-package socket exhaustion despite v0.54.1

🚨 CRITICAL CHANGES:
- Activation threshold: 100 → 1 pending operation (configurable)
- Add socket utilization trigger: >10% usage activates buffering
- Add environment variables:
  - BRAINY_BUFFER_THRESHOLD=1 (when to start buffering)
  - BRAINY_FORCE_BUFFERING=true (force enable)
- Add comprehensive logging with emojis for visibility:
  - '🚨 HIGH-VOLUME MODE ACTIVATED 🚨' when buffering starts
  - '🚀 BATCH FLUSH: N items → 1 bulk S3 operation' for batch writes
  - '📈 BUFFER GROWTH: N items buffered' every 100 additions

PROBLEM: v0.54.1 buffering not activating with 7,500 pending requests
SOLUTION: Activate buffering at first sign of load (1+ pending operations)

This should immediately activate buffering in bluesky-package production.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@soulcraft/brainy",
-  "version": "0.54.1",
+  "version": "0.54.2",
   "description": "A vector graph database using HNSW indexing with Origin Private File System storage",
   "main": "dist/index.js",
   "module": "dist/index.js",