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/convenience_in_taxation.md

@@ -0,0 +1,30 @@
+---
+entity_slug: convenience_in_taxation
+entity_type: Principle
+vsm_system: S3
+type_rationale: Convenience in taxation is an abstract rule that Smith proposes should
+  hold across all tax systems, making it a theoretical principle rather than a concrete
+  entity or process.
+vsm_rationale: This principle operates within the management system by guiding how
+  resources should be extracted from the economy through taxation in ways that optimize
+  operational control and minimize disruption to productive activities.
+classified_at: '2026-02-23T10:56:41.835870'
+---
+
+# Classification: Convenience In Taxation
+
+## Entity Type
+
+Principle
+
+## VSM System
+
+S3
+
+## Type Rationale
+
+Convenience in taxation is an abstract rule that Smith proposes should hold across all tax systems, making it a theoretical principle rather than a concrete entity or process.
+
+## VSM Rationale
+
+This principle operates within the management system by guiding how resources should be extracted from the economy through taxation in ways that optimize operational control and minimize disruption to productive activities.