feat(ground): inspect regional execution event ledgers

[d-sorgcodexagent]

What changed

• project validated ground discontinuity events and regional surface transitions into matched PyQt6/React engineering ledgers
• show explicit SI time, position, before/after linear velocity, before/after angular velocity, frame, event sequence/type, and from/to region/surface identity
• retain the full validated evidence envelope while bounding rendered rows to 256 and disclosing the exact shown/total count
• use tabbed native inspection and collapsed browser tables to keep the result surface manageable
• preserve empty ledgers for null-result evidence and retain partial-endpoint warnings/censorship
• update campaign manifest, SPEC, and canonical handoffs in the implementation commit

Why

The prior readback exposed qualified summary metrics but not the validated event/transition evidence needed to diagnose bounces and material-boundary changes. This slice adds inspection without executing or approximating physics in either UI.

Validation

• implementation review: 208 Python tests and 111 React files / 692 tests passed
• independent subreview found and fixed one P2 state mismatch, then approved the amended head
• independent root verification: 5 Python and 6 React focused tests passed
• Ruff/format, strict MyPy, TypeScript, zero-warning ESLint, production build, manifest, docs governance, size budgets, placeholder and diff checks passed

Remaining work

Trajectory-sample inspection, lossless export, executor invocation, playback, measured calibration, compiled parity, downstream parity, protected review/release gates remain open. This does not complete #4271 or #4267.

Addresses #4271
Part of #4267

[dieterolson]

Consolidated into #4409. Closing to reduce CI/CD runner load.