fix(rdp): revalidate focused selects from context

[abrichr]

What changed

• During the second, post-focus phase of opaque-remote SELECT_OPTION, require the retained template or independent relational landmarks.
• Do not use the control's current OCR value in that phase because an open option menu can render the same value in both the field and the popup.
• Keep the default resolver ladder unchanged for every other action and phase.

Root cause

The exact-main OpenEMR xrdp/FreeRDP campaign completed nine countable trials. All three healthy trials halted at the first Title selection because focusing the native select exposed two OCR candidates for Unassigned. All six visual-drift and wrong-session fault trials halted safely, the independent REST+SQL oracle confirmed no unintended write, and model calls were zero. The runtime was correctly conservative, but it used evidence that becomes intentionally non-unique after focus.

The post-focus phase already has independent retained landmarks and a fresh remote actuation frame. This change uses those stable signals. If the template and landmarks cannot prove the field, execution still halts.

Validation

• 164 passed, 15 skipped: RDP backend, resolver, and replayer suites.
• Strict mypy passes for runtime/replayer.py and runtime/resolver.py.
• Ruff, format, and diff checks pass.
• A focused regression proves that the duplicated value is not consulted after focus, a retained field-label landmark re-resolves the field, and exact selected-value verification still passes.

No production-readiness claim or sandbox activation is included in this PR. The exact-main 3+3+3 campaign will be rerun after merge.