Is seeing the death of a dear person and scattering sugar in front of the door on Friday after performing Istikhara prayer an indication of a good ending?

Performing Qiyam al-Layl (night prayers) and Istikhara (prayer for guidance) are divine blessings. The Prophet encouraged Qiyam al-Layl, stating that it is the practice of the righteous, a means of drawing closer to Allah, and an expiation for sins, as in the Hadith: "You should observe Qiyam al-Layl, for it was the practice of the righteous before you, and it is a means of drawing closer to Allah the Almighty, a deterrent from sin, and an expiation for misdeeds." And the verse states: "And from [parts of] the night, pray with it as additional [worship] for you; it is expected that your Lord will resurrect you to a praised station."

As for interpreting dreams, this is not within our specialization. You may consult trustworthy specialists in that regard.

Regarding death on Friday or its eve, it is a sign of a good end, as mentioned by Al-Albani in his book Ahkam al-Jana'iz, citing the Hadith: "There is no Muslim who dies on Friday or the night of Friday except that Allah protects him from the trial of the grave."