feat(example): add L2 classifications for 823/988 WoN entities (S3.4)

Batch classification via OpenRouter (claude-sonnet-4). 165 entities
remain unclassified due to credit exhaustion; incremental skip means
a follow-up run will complete them automatically.

Type × VSM matrix (823 entities):
                  S1   S2   S3  S3*   S4   S5
  Element         86   75   58   21   43   32  (315 total, 38%)
  Process         39   42   37   17   67   24  (226 total, 28%)
  Institution      4   12   30   24    .   52  (122 total, 15%)
  Principle        3    7   15    2   43   32  (102 total, 12%)
  Relation         2   14    5    5   22   10   (58 total,  7%)
  Matrix fill: 29/30 cells (Institution/S4 empty — expected)

Metrics updated: type_entropy=2.0936, vsm_type_matrix_cells=29

Also:
- BatchEvaluator gains delay_seconds param for rate-limited providers
- classify CLI gains --rpm option (--rpm 10 for Gemini free tier)
- history.write_metrics_file now handles non-float metric values
  (type_distribution is a dict, was crashing round())
- run_entity_classification forwards delay_seconds to BatchEvaluator
- classify-links and graph commands added by user (entities --by-type,
  graph --format mermaid/dot, classify-links for Relation enrichment)

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

examples/infospace-with-history/output/classifications/country_gentlemen_versus_merchants.md

@@ -0,0 +1,31 @@
+---
+entity_slug: country_gentlemen_versus_merchants
+entity_type: Relation
+vsm_system: S5
+type_rationale: This entity represents a structural dependency between two distinct
+  social groups (country gentlemen and merchants) and their contrasting influences
+  on trade policy formation, functioning as a connector that explains how different
+  economic interests shape political outcomes.
+vsm_rationale: This contrast operates at the policy level where ultimate authority
+  and purpose in political economy are determined, as it concerns how different social
+  groups influence the fundamental direction and identity of trade policy systems.
+classified_at: '2026-02-23T10:57:09.215264'
+---
+
+# Classification: Country Gentlemen Versus Merchants
+
+## Entity Type
+
+Relation
+
+## VSM System
+
+S5
+
+## Type Rationale
+
+This entity represents a structural dependency between two distinct social groups (country gentlemen and merchants) and their contrasting influences on trade policy formation, functioning as a connector that explains how different economic interests shape political outcomes.
+
+## VSM Rationale
+
+This contrast operates at the policy level where ultimate authority and purpose in political economy are determined, as it concerns how different social groups influence the fundamental direction and identity of trade policy systems.