Add /res pmirror to mirror flags between players

[RICE0707]

Mirrors one player's flags onto another player inside the same residence.

/res pmirror [Residence] [Source player] [Target player]

Residence name can be omitted while standing inside one. /res mirror already handles residence-to-residence; this covers the player-to-player case, which previously meant one /res pset per flag.

Merges, does not replace — target flags with no counterpart on the source are left alone, same as applyTemplate() does for /res mirror. For an exact copy, run /res pset [residence] [target] removeall first.

Flags are replayed through the existing setPlayerFlag() rather than copying the map directly, so trusted-residence bookkeeping, the raid lock, and ResidenceFlagChangeEvent all still fire. Permission handling matches /res pset.

Includes translations for all 7 language files. English.yml is untouched — it is generated at runtime from the lm enum defaults.