feat(llm): add OpenAI adapter, entity archive policy, process chapters 5-7

Add OpenAIAdapter for the OpenAI chat completions API (apikey-chatgpt.txt
or OPENAI_API_KEY). Set default model to arcee-ai/trinity-large-preview:free
for the infospace pipeline and increase max_tokens from 4096 to 8192.

Reprocess chapter 05 with Trinity Large (was Gemini: 1 truncated entity,
now 19 complete entities). Process chapters 06 (Aurora Alpha, 10 entities)
and 07 (Trinity Large, 15 entities including regenerated violent-policy.md).
Canonical set now at 85 unique entities.

Add entity archive policy: entities are never silently deleted. Retired
entities move to output/entities/archive/ with a dated reason header.
New CLI option: --archive-entity <slug> --reason "...". The --list
output shows the archive count alongside the canonical set.

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

examples/infospace-with-history/output/entities/stock.md

@@ -0,0 +1,19 @@
+# stock
+
+**Definition**  
+Stock refers to the accumulated capital, materials, and resources that an entrepreneur or employer invests in order to employ labour and produce commodities. It includes both the physical inputs (raw materials, tools) and the financial capital required to sustain production until the product is sold.
+
+**Source Chapter**  
+*The Wealth of Nations*, Book 1, Chapter 6.
+
+**Context**  
+Smith discusses stock when describing how “stock has accumulated in the hands of particular persons” and how it is employed to “set to work industrious people.” He links stock to the ability to earn profit and to the wages paid to labourers.
+
+**Economic Domain**  
+Accumulation
+
+**Smith’s Original Wording**  
+> “As soon as stock has accumulated in the hands of particular persons, some of them will naturally employ it in setting to work industrious people…”
+
+**Modern Interpretation**  
+In modern terms, stock is synonymous with capital stock—the total value of physical and financial assets used in production. It is a key input in the production function and a determinant of a firm’s capacity to generate profit.