feat: import experimental CIG graph mechanics

docs/migration/import-ledger.md

@@ -52,7 +52,7 @@ Empty placeholder directories (no tracked source): `packages/ts-*`, top-level `e
 | Repository | Verified source SHA in this clone? | Destination claimed historically | Status | Notes |
 |------------|-------------------------------------|----------------------------------|--------|-------|
 | TS-Core | `3ef48ad00efef8659ad0981d71de509a9827f584` | `src/thinking_system/core/typed_tension/` | **PARTIALLY_IMPORTED** | Domain-neutral typed tension kernel imported with its focused test and example; legacy Python application layers, Rust acceleration, CLI, Z3, Grok, UI, and Kernel Wave 12 surfaces remain unimported |
-| cig-ts-engine | Not verified here | `packages/ts-graph` | **INSPECTED** / **PLANNED** | Graph lives in `core/graph` |
+| cig-ts-engine | `71d91a6a0cdc9e7a5439df972130596f0bae5d2f` | `src/thinking_system/graph/cig/` | **PARTIALLY_IMPORTED** | Core graph models, deterministic propagation, edge tension, derivative observer, representational radius, context-split proposal, YAML IO, seed graph and focused tests imported; CLI, plotting, reports, Obsidian export and generated artifacts remain outside |
 | TS-Benchmarks | Not verified here | `benchmarks/` | **PLANNED** | `benchmarks/suites` empty |
 | ts-chat-language | Not verified here | `packages/ts-language` | **INSPECTED** / **PLANNED** | TSLC-like code in `core/language/tslc.py` is in-tree monorepo code; full satellite port not evidenced |
 | TensionForge | Not verified here | `engines/tension-forge` | **PLANNED** (satellite); in-tree `inference/tension_forge/` is separate | Empty `engines/tension-forge/` |

docs/migration/sources/cig-ts-engine.md

@@ -0,0 +1,68 @@
+# cig-ts-engine consolidation record
+
+## Source
+
+- Repository: `BoggersTheFish/cig-ts-engine`
+- Source branch: `master`
+- Source commit: `71d91a6a0cdc9e7a5439df972130596f0bae5d2f`
+- Licence: MIT
+
+## Imported surface
+
+The deterministic, domain-neutral CIG mechanics were imported into:
+
+`src/thinking_system/graph/cig/`
+
+Imported functionality:
+
+- validated node and edge models
+- mutable deterministic CIG graph state
+- deterministic activation propagation and relaxation
+- edge-local and total tension measurement
+- finite-difference derivative-meaning observer
+- representational-radius measurement
+- overloaded-node localisation
+- non-mutating context-split proposals
+- tension-reduction versus complexity-cost acceptance rule
+- context-split application
+- YAML graph loading and saving
+- the hand-authored demonstration seed graph
+- focused tests for the imported surface
+
+## Adaptation
+
+Imports were changed from `cig` to
+`thinking_system.graph.cig`.
+
+The demonstration graph was renamed from:
+
+`examples/ts_core.yaml`
+
+to:
+
+`examples/cig_ts_core.yaml`
+
+The implementation remains an experimental graph family alongside the existing
+Thinking System universal graph. It has not replaced that graph implementation.
+
+## Deliberately not imported
+
+- Typer CLI
+- matplotlib visualisation
+- proof-report generation
+- Obsidian export
+- generated PNG files
+- generated proof-bank documents
+- generated Obsidian vault contents
+- symbolic or biographical demonstration scripts
+
+Those surfaces are application, presentation, or generated-output layers rather
+than required graph mechanics.
+
+## Current status
+
+**PARTIALLY_IMPORTED**
+
+The core experimental graph mechanics are present and tested. The satellite
+must remain unarchived until its excluded surfaces are explicitly classified as
+obsolete, historical, independently maintained, or worth importing.