Add minimal typed builder-lineage core

CHANGELOG.md

@@ -7,6 +7,13 @@ later entries are regular releases.
 
 ## Unreleased
 
+### Added
+
+- A pure typed builder-lineage contract with immutable exact targets, validated
+  contribution chains, explicit comment history and authority accounts, and
+  contributor-aware reviewer admission. Includes a standalone init support
+  module; live consumers will adopt the contract in a later stage.
+
 ### Fixed
 
 - Coworker fast-search responses with `source_id`, missing titles, or `Text`

code-mower-package-manifest.json

@@ -372,6 +372,11 @@
       "source": "src/code_mower/builder_experiment.py",
       "target": "src/code_mower/builder_experiment.py"
     },
+    {
+      "kind": "core",
+      "source": "src/code_mower/builder_lineage.py",
+      "target": "src/code_mower/builder_lineage.py"
+    },
     {
       "kind": "core",
       "source": "src/code_mower/builder_runs.py",
@@ -2056,6 +2061,11 @@
       "kind": "workflow",
       "source": "generated",
       "target": "templates/workflows/trailer-comment-labeler.yml.j2"
+    },
+    {
+      "kind": "core",
+      "source": "tools/builder_lineage.py",
+      "target": "tools/builder_lineage.py"
     }
   ],
   "mode": "materialize",