Add rolemaster situational modifier modal

README.md

@@ -81,7 +81,8 @@ Rolemaster support:
 - Open-ended percentile expressions such as `d100!+85`
 - Conditional `FumbleRange` handling for open-ended percentile skills and skill-group defaults
 - Persisted and validated automatic retry toggle for open-ended percentile skills; only eligible Rolemaster skills can enable it
-- Backend/API support for one-shot situational modifiers on Rolemaster skill rolls; the temporary modifier is applied to both the first attempt and any automatic retry attempt
+- Rolemaster skill rolls open a modal prompt before rolling so the player can apply a one-shot situational modifier; the prompt autofocuses, supports Enter and Escape, and closes when clicking outside it
+- One-shot situational modifiers are transient Rolemaster-only roll inputs; the temporary modifier is applied to both the first attempt and any automatic retry attempt
 - Automatic retry windows for eligible open-ended skills: results `76-90` retry once with `+5`, and results `91-110` retry once with `+10`
 - Open-ended high chaining and low-end subtraction with ordered die metadata in roll detail
 - Compact log badges and summaries for open-ended, retry, and fumble-related events, including `Retry +5` and `Retry +10`