feat(pipeline): pipeline_version v2, migration 062, docs + 71 tests

- Add PIPELINE_VERSION=2 constant and pipeline_version column to
  canonical_controls and canonical_processed_chunks (migration 062)
- Anthropic API decides chunk relevance via null-returns (skip_prefilter)
- Annex/appendix chunks explicitly protected in prompts
- Fix 6 failing tests (CRYP domain, _process_batch tuple return)
- Add TestPipelineVersion + TestRegulationFilter test classes (10 new tests)
- Add MkDocs page: control-generator-pipeline.md (541 lines)
- Update canonical-control-library.md with v2 pipeline diagram
- Update testing.md with 71-test breakdown table

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

backend-compliance/compliance/services/control_generator.py

@@ -53,6 +53,11 @@ LLM_TIMEOUT = float(os.getenv("CONTROL_GEN_LLM_TIMEOUT", "180"))
 
 HARMONIZATION_THRESHOLD = 0.85  # Cosine similarity above this = duplicate
 
+# Pipeline version — increment when generation rules change materially.
+# v1: Original (local LLM prefilter, old prompt)
+# v2: Anthropic decides relevance, null for non-requirement chunks, annexes protected
+PIPELINE_VERSION = 2
+
 ALL_COLLECTIONS = [
     "bp_compliance_ce",
     "bp_compliance_gesetze",
@@ -1663,7 +1668,7 @@ Kategorien: {CATEGORY_LIST_STR}"""
                         license_rule, source_original_text, source_citation,
                         customer_visible, generation_metadata,
                         verification_method, category, generation_strategy,
-                        target_audience
+                        target_audience, pipeline_version
                     ) VALUES (
                         :framework_id, :control_id, :title, :objective, :rationale,
                         :scope, :requirements, :test_procedure, :evidence,
@@ -1672,7 +1677,7 @@ Kategorien: {CATEGORY_LIST_STR}"""
                         :license_rule, :source_original_text, :source_citation,
                         :customer_visible, :generation_metadata,
                         :verification_method, :category, :generation_strategy,
-                        :target_audience
+                        :target_audience, :pipeline_version
                     )
                     ON CONFLICT (framework_id, control_id) DO NOTHING
                     RETURNING id
@@ -1702,6 +1707,7 @@ Kategorien: {CATEGORY_LIST_STR}"""
                     "category": control.category,
                     "generation_strategy": control.generation_strategy,
                     "target_audience": json.dumps(control.target_audience) if control.target_audience else None,
+                    "pipeline_version": PIPELINE_VERSION,
                 },
             )
             self.db.commit()
@@ -1728,11 +1734,13 @@ Kategorien: {CATEGORY_LIST_STR}"""
                     INSERT INTO canonical_processed_chunks (
                         chunk_hash, collection, regulation_code,
                         document_version, source_license, license_rule,
-                        processing_path, generated_control_ids, job_id
+                        processing_path, generated_control_ids, job_id,
+                        pipeline_version
                     ) VALUES (
                         :hash, :collection, :regulation_code,
                         :doc_version, :license, :rule,
-                        :path, :control_ids, CAST(:job_id AS uuid)
+                        :path, :control_ids, CAST(:job_id AS uuid),
+                        :pipeline_version
                     )
                     ON CONFLICT (chunk_hash, collection, document_version) DO NOTHING
                 """),
@@ -1746,6 +1754,7 @@ Kategorien: {CATEGORY_LIST_STR}"""
                     "path": processing_path,
                     "control_ids": json.dumps(control_ids),
                     "job_id": job_id,
+                    "pipeline_version": PIPELINE_VERSION,
                 },
             )
             self.db.commit()