feat: Link-Taxonomie u3 - kb/concepts/ vollstaendig gelabelt

Files changed:
- kb/concepts/Ambient Environment Dependency.md
- kb/concepts/Anti-Cramming Heuristic.md
- kb/concepts/Audit Trail.md
- kb/concepts/BM25.md
- kb/concepts/Bulk Operations.md
- kb/concepts/CI Integration.md
- kb/concepts/CPPC.md
- kb/concepts/Checkpoint Audit.md
- kb/concepts/Claude Code Auto Mode.md
- kb/concepts/Command Round-Trip Integrity.md
- kb/concepts/Confidence Scoring.md
- kb/concepts/Consolidation Tiers.md
- kb/concepts/Content Quality Control.md
- kb/concepts/Context Isolation.md
- kb/concepts/Contradiction Resolution.md
- kb/concepts/Cross-platform Agent Skills.md
- kb/concepts/Crystallization.md
- kb/concepts/Delete Rather Than Anonymize.md
- kb/concepts/Denylist over Allowlist.md
- kb/concepts/Detect-Repair Asymmetry.md
- kb/concepts/Diff-Reviewable Agent Edits.md
- kb/concepts/Dual Licensing by File Plan.md
- kb/concepts/Entity Extraction.md
- kb/concepts/Episodic Memory.md
- kb/concepts/Event-Driven Automation.md
- kb/concepts/Filter on Ingest.md
- kb/concepts/Forgetting.md
- kb/concepts/Graph Traversal.md
- kb/concepts/Green Suite Blind Spot.md
- kb/concepts/Hooks.md
- kb/concepts/Hybrid Search.md
- kb/concepts/Implementation Spectrum.md
- kb/concepts/Index Scaling.md
- kb/concepts/Issue Label Scheme.md
- kb/concepts/Iteration and Cost Limits.md
- kb/concepts/KB Migration.md
- kb/concepts/KB Stack Versioning.md
- kb/concepts/Knowledge Compounding.md
- kb/concepts/Knowledge Graph.md
- kb/concepts/LLM Wiki Pattern.md
- kb/concepts/Lint Workflow.md
- kb/concepts/MCP-Leseserver.md
- kb/concepts/Mass-Update Gate.md
- kb/concepts/Memory Lifecycle.md
- kb/concepts/Mesh Sync.md
- kb/concepts/Modbus.md
- kb/concepts/Multi-Agent Collaboration.md
- kb/concepts/Naming Convention Conflict.md
- kb/concepts/OKF Compatibility.md
- kb/concepts/Optional Instance Context File.md
- kb/concepts/Personalization Plane.md
- kb/concepts/Privacy and Governance.md
- kb/concepts/Procedural Memory.md
- kb/concepts/Publish-Remote Gate.md
- kb/concepts/Quality Scoring.md
- kb/concepts/Quality and Self-Correction.md
- kb/concepts/RAG.md
- kb/concepts/Reciprocal Rank Fusion.md
- kb/concepts/SSD TRIM.md
- kb/concepts/Scale Ceiling.md
- kb/concepts/Self-Healing.md
- kb/concepts/Semantic Lint Automation.md
- kb/concepts/Semantic Memory.md
- kb/concepts/Session Orientation.md
- kb/concepts/Shared vs Private.md
- kb/concepts/Split Merge Reclassify.md
- kb/concepts/Split Threshold.md
- kb/concepts/Structural Enforcement over Documented Rule.md
- kb/concepts/Stub Threshold.md
- kb/concepts/Supersession.md
- kb/concepts/Three-Layer Architecture.md
- kb/concepts/Token Economics.md
- kb/concepts/Typed Relationships.md
- kb/concepts/User Management.md
- kb/concepts/Vector Search.md
- kb/concepts/Work Coordination.md
- kb/concepts/Workflow Extraction.md
- kb/concepts/Workflow Orchestration.md
- kb/concepts/Working Memory.md
- kb/concepts/Write-Once Frontmatter Fields.md
- kb/log.md
- work/link-taxonomy-migration/glossary.md

work/link-taxonomy-migration/glossary.md

@@ -4,6 +4,22 @@ Vocabulary decided while processing one page, carried forward so u3 (concepts) a
 (projects/people/comparisons) do not re-decide it. Add to this file before dispatching the next
 unit or sub-session.
 
+## Mechanism correction, discovered in u3 (concepts): `xref add` is always safe
+
+`xref add --a A --b B --rel X` **only ever touches page A** - it upserts (idempotent by target),
+so calling it on a pair that already has an unlabelled or even a differently-labelled entry just
+relabels it in place. `xref remove` is the only bidirectional, destructive call (strips the pair
+from **both** pages' `related:` and matching body lines). u1 already learned to sequence removes
+before adds per pair; u3 goes further and mostly **stops calling `xref remove` at all** for
+drift-only entries. Standing policy for the rest of this migration: when a frontmatter `related:`
+entry does not deserve its most literal label, relabel it with the best authorised fit - `see-also`
+if truly nothing fits - via `xref add`, rather than removing it. Only remove when the entry is a
+misplaced mention with nothing worth keeping on either side, and only after confirming (grep) that
+the target page carries no reciprocal reference that a bidirectional strip would destroy. This
+avoided several near-misses in u3 (`CPPC`/`amd-pstate` already carried `amd-pstate implements
+CPPC` from u1 - removing would have destroyed it; relabelled as `CPPC mechanism amd-pstate`
+instead).
+
 ## Unit sizing correction (2026-09-02)
 
 u1 as written in `plan.md` (`kb/entities/systems, tools, technologies`, estimated ~45 pages) is