Sprint 1: project skeleton, type system, and all architecture specs

- src/types.hpp: complete UCWM type system in C++20 — 19 enums, 11 facet
  data types, all core structs (CanonicalObject, Constraint, Facet,
  GateSignal, WorldState, etc.) with full JSON round-trip serialization
- src/main.cpp: smoke test — constructs apple-problem WorldState by hand,
  serializes to JSON
- tests/test_types.cpp: 19 tests, 123 assertions, all passing
- CMakeLists.txt: CMake + CPM build with nlohmann/json, spdlog, Catch2
- schemas/: JSON Schema contracts for all UCWM data types
- gates/, specialists/, resolver/, synthesis/: language-agnostic interface
  contracts and domain specs for all pipeline layers
- docs/: architecture, vocabulary, decision matrices, roadmap (6 phases,
  28 sprints), sprint_001, implementation_constraints

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

schemas/provenance.json

@@ -0,0 +1,80 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "ucwm/schemas/provenance.json",
+  "title": "Provenance",
+  "description": "Tracks where every fact, object, facet, and constraint came from. Enables failure localization and explainability.",
+  "type": "object",
+  "required": ["provenance_id", "record_type", "source_module", "timestamp"],
+  "additionalProperties": false,
+  "properties": {
+    "provenance_id": {
+      "type": "string",
+      "description": "Unique identifier. Format: P{sequence}"
+    },
+    "record_type": {
+      "type": "string",
+      "enum": ["object_proposal", "facet_attachment", "constraint_emission", "resolver_operation", "object_merge", "object_split", "synthesis_step"],
+      "description": "What kind of operation created this provenance record."
+    },
+    "source_module": {
+      "type": "string",
+      "description": "Module ID that triggered this event."
+    },
+    "input_refs": {
+      "type": "array",
+      "items": { "type": "string" },
+      "description": "IDs of objects, facets, or constraints that were inputs to the operation.",
+      "default": []
+    },
+    "output_refs": {
+      "type": "array",
+      "items": { "type": "string" },
+      "description": "IDs of objects, facets, or constraints produced by the operation.",
+      "default": []
+    },
+    "evidence_span": {
+      "type": "object",
+      "description": "Text span that provided evidence for this operation.",
+      "properties": {
+        "text": { "type": "string" },
+        "start": { "type": "integer" },
+        "end": { "type": "integer" }
+      }
+    },
+    "confidence": {
+      "type": "number",
+      "minimum": 0.0,
+      "maximum": 1.0
+    },
+    "timestamp": {
+      "type": "string",
+      "description": "ISO 8601 timestamp of when this operation occurred."
+    },
+    "notes": {
+      "type": "string",
+      "description": "Optional free-text note. For debugging only — not part of the reasoning chain."
+    }
+  },
+  "examples": [
+    {
+      "provenance_id": "P1",
+      "record_type": "object_proposal",
+      "source_module": "entity_specialist",
+      "input_refs": [],
+      "output_refs": ["E1"],
+      "evidence_span": { "text": "Alice", "start": 0, "end": 5 },
+      "confidence": 0.97,
+      "timestamp": "2026-05-01T00:00:00Z"
+    },
+    {
+      "provenance_id": "P4",
+      "record_type": "resolver_operation",
+      "source_module": "resolver",
+      "input_refs": ["C1", "C2", "C3"],
+      "output_refs": ["Q_alice_final"],
+      "confidence": 0.99,
+      "timestamp": "2026-05-01T00:00:01Z",
+      "notes": "Arithmetic resolution: 5 - 2 = 3"
+    }
+  ]
+}