[VV0003]

Summary

Temporarily withdraws the multi-PE integration squash-merged in #292 (b5fbae1) from linx, per the team's decision to hold the multi-PE stack off the stable line for now.

• Removes the multi-PE runtime API, PE-domain participation, TileArray participant masks, hosted gfrun adapter and their tests
• Keeps fix(tileop): support CubeM32 binary slot assembly #289 (CubeM32 binary slot assembly) and fix: reject mismatched TCMP/TSEL physical shapes #291/test: guard narrow TCMP constructors and mandatory LB0 codegen #293 (TCMP/TSEL shape contract, narrow TCMP constructors) untouched
• The full integrated content is preserved on 0.59@1153ea6 and on codex/multi-pe-tileop-20261013@6ade6f4 for the upcoming 0.59 integration line
• Re-landing later is a plain revert of this revert (or a fresh PR from the 0.59 line)

Validation

• Revert applied with no conflicts; tree equals c150817 (pre-Multi-PE runtime, PE-domain participation and hosted gfrun adapter #292 linx) plus test: guard narrow TCMP constructors and mandatory LB0 codegen #293 exactly
• engine contract, version header and issue290 Python suites PASS