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/agricultural_productivity.md

@@ -0,0 +1,31 @@
+---
+entity_slug: agricultural_productivity
+entity_type: Element
+vsm_system: S1
+type_rationale: Agricultural productivity is a measurable characteristic or capacity
+  of agricultural land and labor that persists as a stock-like property, representing
+  the efficiency potential that exists independently rather than being a process or
+  activity itself.
+vsm_rationale: Agricultural productivity directly relates to the primary productive
+  operations of the economy, as it measures the efficiency of the fundamental agricultural
+  labor and land use that constitutes the basic productive activities Smith analyzes.
+classified_at: '2026-02-23T10:42:07.242630'
+---
+
+# Classification: Agricultural Productivity
+
+## Entity Type
+
+Element
+
+## VSM System
+
+S1
+
+## Type Rationale
+
+Agricultural productivity is a measurable characteristic or capacity of agricultural land and labor that persists as a stock-like property, representing the efficiency potential that exists independently rather than being a process or activity itself.
+
+## VSM Rationale
+
+Agricultural productivity directly relates to the primary productive operations of the economy, as it measures the efficiency of the fundamental agricultural labor and land use that constitutes the basic productive activities Smith analyzes.