Rebase/validation checkpoint for head 5c05be4605:

• rebased the formatting-only commit onto current upstream b22e2e58b2; git range-diff reports the patch as exact (=)
• whole-repository Runic passed locally
• the official GROUP=Integrators_I harness passed locally on the coherent #4064 + #4066 validation stack
  • Step Limiter Tests: 251/251
  • Discontinuity Detection Tests: 28/28
  • Testing OrdinaryDiffEq tests passed
  • total group runtime: 2882.56 seconds
• fetched both upstream and the fork immediately before updating the branch; upstream was still b22e2e58b2, and the remote branch was still our prior 0172415aaf head with no contributor commits, so the rebased head was pushed with an exact-SHA --force-with-lease

The #4066 commit remains test-only validation context and is not included in this branch.

Clean-master bisect refinement (independent checkout at b22e2e58b2):

• the aggregate whole-tree Runic failure begins at 408a7a30fe (disco optimizations);
• lib/OrdinaryDiffEqCore/src/disco.jl and test/Integrators_I/disco_tests.jl are first bad at that same commit;
• lib/OrdinaryDiffEqCore/src/integrators/controllers.jl becomes nonconforming later at 80d7e74c82;
• all three relevant files pass at parent c538565b25;
• formatting exact clean master produces the same 38-insertion/34-deletion tree as this PR head, and whole-tree Runic then passes.

This confirms #4064 is the existing focused fix for the complete clean-master formatter regression; no duplicate PR was opened.

One-hour terminal CI audit for rebased head 5c05be4605: 9 checks succeeded, 3 were skipped, and 241 failed. The hosted Runic format check is green; none of the 241 failures is in this formatting patch.

Exact breakdown:

• 127 sublibrary jobs stopped before tests (126 in julia-buildpkg, one developing local Core sources). Representative logs from both paths show registered SciMLBase 3.39.1 versus the current local 3.40 floor fixed by Restore SciMLBase 3.39 compatibility for owner imports #4066.
• all 44 root test jobs stopped before tests (29 in julia-buildpkg, 15 developing in-repo sources) at the same compatibility boundary.
• all 12 external downstream failure logs were checked individually; every one contains a SciMLBase unsatisfiable requirement before downstream tests.
• documentation stopped at the same resolver boundary.
• 56 sublibrary downgrade jobs and the root downgrade job stopped inside the downgrade resolver before tests.

The actual formatting checks are green: hosted Runic / Runic Format Check, Runic suggestions, and Typos all succeeded. Local whole-tree Runic and the official 48-minute Integrators_I validation (251/251 Step Limiter, 28/28 DISCO) remain the behavior gate. The rebased #4066 compatibility prerequisite is now pushed separately at 661bd35c64; no dependency change belongs in this formatting-only PR.