Adds the implementation plan for the location-override feature and folds in
ce-doc-review findings: a panel-open sync gap (pin didn't render on reopen
with pre-existing coordinates), keyboard/ARIA accessibility gaps in the
search-results list and mismatch flag, a shared MAP_STYLE module to remove
duplication drift risk, and a corrected Open-Meteo risk/mitigation split.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
