feat(v4.5): add tests + CMake integration for all 3 new modules

Tests (48 new test cases total):
- test_draft_analysis.cpp: 18 tests (draft angle, classification, report, distribution)
- test_incremental_mesh.cpp: 15 tests (rebuild, invalidate, cache, merge, memory)
- test_kinematic_chain.cpp: 27 tests (Grashof, Freudenstein, gear ratio, 5 cam motions)

Build system:
- src/CMakeLists.txt: +draft_analysis, +incremental_mesh, +kinematic_chain
- tests/brep/CMakeLists.txt: +3 new test targets

Docs:
- 剩余路线图: v4.5 → 🚧

docs/23-剩余路线图.md

@@ -20,7 +20,7 @@ v4.1 ──→ v4.2 ──→ v4.3 ──→ v4.4 ──→ v4.5 ──→ v5.0
 
 ---
 
-## v4.5 — 实用增强
+## v4.5 — 实用增强 🚧
 
 | 项目 | 工作量 | 说明 |
 |------|--------|------|