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/llm-as-parser-fallback.md

@@ -0,0 +1,33 @@
+# Pattern: LLM-as-Parser with Structured Fallback
+
+## Symptom
+A workflow asks an LLM to parse, classify, or extract information from unstructured input. Sometimes the output is correct but poorly formatted; sometimes it is wrong or inconsistent. Downstream nodes cannot rely on it without a validation step.
+
+## Affected Projects
+- Cyber Tips Newsletter pipeline
+- Proxmox VE snapshot summarizer
+- Email inbox triage agent
+- Monthly IT newsletter generator
+
+## Root Cause
+Using an LLM as a parser combines the power of fuzzy reasoning with the fragility of probabilistic output. Without a structured fallback, the pipeline is brittle.
+
+## Standard Fix
+1. Ask the LLM for structured output (JSON/schema) when possible.
+2. Add a validation layer that checks required fields and value ranges.
+3. Add a regex or rule-based extraction fallback for common failure modes.
+4. For classification tasks, maintain a small deterministic ruleset for high-confidence cases and use the LLM only for ambiguous cases.
+5. Log parse failures to identify when the LLM is drifting.
+
+## When to Apply
+- Any workflow where an LLM extracts or classifies data that downstream nodes consume.
+- Any pipeline where consistency matters more than creative interpretation.
+
+## Verification
+- Test with malformed, ambiguous, and adversarial inputs.
+- Confirm downstream nodes receive validated, structured data.
+- Review parse-failure logs periodically.
+
+## Related Patterns
+- `ollama-structured-output-fallback`
+- `json-escaping-downstream-api`