feat: Dreaming engine for periodic memory consolidation

[helal-muneer]

Summary

Closes #577

Implements Dreaming functionality — periodic memory consolidation and tier promotion that bridges LanceDB Pro's existing , , and into OpenClaw's dreaming lifecycle.

Three-Phase Dreaming Cycle

💤 Light Sleep — Decay + Tier Re-evaluation

• Scans recent memories (configurable lookback, default 7 days)
• Computes Weibull decay scores via decayEngine.scoreAll()
• Evaluates tier transitions via tierManager.evaluateAll()
• Applies promotions/demotions via store.patchMetadata()

🧠 Deep Sleep — Working → Core Promotion

• Filters Working-tier memories by composite score and access count
• Boosts importance (+20%) for qualifying memories
• Promotes to Core tier via patchMetadata()

💫 REM — Pattern Detection & Reflection

• Analyzes category clustering across tiers
• Detects high-importance category patterns
• Creates reflection memories (category: "reflection") with discovered patterns

Changes

File	Description
src/dreaming-engine.ts	New — dreaming engine factory with 3-phase cycle
openclaw.plugin.json	Add dreaming config schema + UI hints
index.ts	Wire dreaming into service lifecycle, add to PluginConfig

Bug Fix Included

• resolveEnvVars() now returns empty string instead of throwing when env var is missing (prevents plugin startup failure when JINA_API_KEY etc. are unset)

Configuration

{
  "dreaming": {
    "enabled": true,
    "timezone": "UTC",
    "storageMode": "inline",
    "verboseLogging": false,
    "phases": {
      "light": { "lookbackDays": 7, "limit": 50 },
      "deep": { "limit": 20, "minScore": 0.5, "minRecallCount": 2 },
      "rem": { "lookbackDays": 30, "limit": 10, "minPatternStrength": 0.6 }
    }
  }
}

Testing

• ✅ Plugin loads successfully with dreaming enabled
• ✅ Dreaming engine initializes on service start
• ✅ Tier transitions apply correctly during light phase
• ✅ Core promotions work during deep phase
• ✅ Pattern detection creates reflection memories in REM phase
• ✅ Graceful error handling per phase (no cascade failures)
• ✅ Cleanup on service stop