Improve pidTuningIdleMinRpmHelp Tooltip text

This phrase is more concise, direct to the point and uses less technical jargon that's better for the end-user that soes not care to what happens under the hood. Please correct me if I defined something wrong.

escaped double quotes chars

better IdleMinRPM tooltip

Thanks to ctzsnooze

Added wiki entry for Dynamic Idle

locales/en/messages.json

@@ -3663,7 +3663,7 @@
         "message": "Dynamic Idle Value [rpm]"
     },
     "pidTuningIdleMinRpmHelp": {
-        "message": "Set this parameter to provide an rpm based floor-value as a safety net against motor desync.<br>A racer might prefer very good response and low rates - therefore a low Dynamic Idle[rpm] and a high Dshot Idle value may be useful. Freestylers and LOS pilots will appreciate very low thrust at idle and might want to use less Dshot Idle value while using a bit more Dynamic Idle[rpm] to avoid desyncs at high rates. Note that the Dynamic Idle[rpm] value always must be less than Dshot Idle value.<br><br>Visit this <a href=\"https://github.com/betaflight/betaflight/wiki/Tuning-Dynamic-Idle\"target=\"_blank\" rel=\"noopener noreferrer\">wiki</a> entry for more info."
+        "message": "Dynamic Idle improves control at low rpm and reduces risk of motor desyncs. It corrects problems caused by airflow speeding up or slowing down the props, improving PID authority, stability, motor braking and responsiveness. The Dynamic Idle rpm should be set to be about 20% below the rpm of your Dshot Idle value (see the $t(tabMotorTesting.message) tab). Usually there is no need to change your DShot idle value from defaults. For longer inverted hang time, DShot idle value and Minimum rpm should be lowered together.<br><br>Visit <a href=\"https://github.com/betaflight/betaflight/wiki/Tuning-Dynamic-Idle\"target=\"_blank\" rel=\"noopener noreferrer\">this wiki entry</a> for more info."
     },
     "pidTuningAcroTrainerAngleLimit": {
         "message": "Acro Trainer Angle Limit"