Remove xbar/noc remnants, rule-based cube-view connectors

- Delete xbar.py and noc.py (TwoDMeshNocComponent) — unused since router mesh
- Remove xbar_v1/noc_2d_mesh_v1 from components.yaml
- Fix pe_to_xbar → pe_to_router in routing exclusion set
- Fix xbar_to_hbm_bw_gbs → hbm_to_router_bw_gbs in report.py
- Update all docstrings/comments referencing xbar/bridge → router mesh
- Cube-view connectors: rule-based _connector_points helper
  - PE↔router: single diagonal line (not chevron)
  - UCIe N/S: 45°→horizontal→45°
  - UCIe E/W: 45°→vertical→45°
  - HBM ports: 45°→horizontal→45°

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/test_probe.py

@@ -1,7 +1,7 @@
 """Tests for H2D writes and PE DMA probe latency invariants.
 
 H2D tests use MemoryWriteMsg (pcie_ep → io_cpu → m_cpu → hbm_ctrl → response).
-PE DMA tests use PeDmaMsg (direct pe_dma → xbar → hbm_ctrl injection).
+PE DMA tests use PeDmaMsg (direct pe_dma → router mesh → hbm_ctrl injection).
 """
 from pathlib import Path
 
@@ -118,7 +118,7 @@ def test_h2d_local_cube_cut_through():
     """H2D to local cube with cut-through should be < 50ns for 4096B.
 
     Full command path: pcie_ep → io_cpu → ucie → noc → m_cpu
-    DMA: m_cpu → noc → xbar → hbm_ctrl (drain once at terminal)
+    DMA: m_cpu → router mesh → hbm_ctrl (drain once at terminal)
     Plus response path back.
     With store-and-forward each hop would serialize; cut-through keeps it low.
     """
@@ -205,7 +205,7 @@ def test_pe_dma_local_bottleneck_hbm():
 
 
 def test_pe_dma_same_half_bottleneck_hbm():
-    """PE DMA pe0→slice1 (same half via xbar_top): bottleneck = HBM effective BW."""
+    """PE DMA pe0→pe1 HBM (same row via router mesh): bottleneck = HBM effective BW."""
     bn = _pe_dma_bottleneck(src_cube=0, src_pe=0, dst_pe=1)
     expected = _hbm_effective_bw()
     assert bn == expected, f"Same-half PE DMA bottleneck {bn}, expected {expected}"