Add cross-project pattern registry for retrieval-augmented generalization

- Create patterns/ directory with README, manifest, and 10 initial patterns
  covering Ollama JSON fallback, API escaping, deprecation, PTY auth,
  queue-poll, LLM-as-parser, credential rotation, reverse proxy binding,
  human approval gates, and transient retry.
- Wire pattern loading into architecture/pipeline.js based on task tags.
- Update architecture/orchestrator.js to load patterns and surface them in
  the system prompt.
- Update MEMORY.md, ARCHITECTURE.md, and CONTEXT.md to document the registry
  and record the decision.

patterns/transient-failure-retry.md

@@ -0,0 +1,31 @@
+# Pattern: Transient Failure Retry and Degradation
+
+## Symptom
+A workflow or agent fails intermittently due to temporary conditions: Ollama model not loaded yet, network blip, rate limit, dependent service restart. A simple rerun often succeeds, but the failure creates noise, lost state, or unnecessary alerts.
+
+## Affected Projects
+- n8n workflows calling Ollama
+- Queue-poll integrations
+- Any service with external dependencies
+
+## Root Cause
+Distributed services are not always available at the moment a caller needs them. Treating every transient failure as a hard error produces false alarms and breaks pipelines that should recover automatically.
+
+## Standard Fix
+1. Classify failures as retryable (network, timeout, 429, 503) or non-retryable (400, 401, schema error).
+2. Apply retry with exponential backoff and jitter for retryable failures.
+3. Set a maximum retry count and a dead-letter/escalation path for persistent failures.
+4. Degrade gracefully if a non-critical dependency fails (e.g., return partial results, skip enrichment).
+5. Distinguish retry events from terminal failures in logs and alerts.
+
+## When to Apply
+- Any integration that calls an external service over the network.
+- Any workflow that has experienced at least one "worked on retry" incident.
+
+## Verification
+- Simulated transient failure triggers retry and eventual success.
+- Non-retryable failure escalates immediately without wasteful retries.
+- Logs clearly show retry count, backoff, and final disposition.
+
+## Related Patterns
+- `queue-poll-async-job`