The ending of Psalm 1 provides great hope for those who delight in the instruction of the Lord:
Not so the wicked;
rather, they are like chaff that wind blows away.
Therefore the wicked will not survive judgment,
nor will sinners, in the assembly of the righteous.
For the Lord cherishes the way of the righteous,
but the way of the wicked is doomed.
— Psalm 1:4-6 (NJPS)
My assumption has always been that the judgement and "assembly of the righteous" look forward to a day in the future such as described in Daniel 12:1-3. But thinking about the Psalm itself, there's no indication that this doesn't provide more immediate hope for those looking for justice. It might be that I'm reading into the Psalm from other (later) writings that were themselves influenced by this Psalm. In other words, Daniel and other authors might have reinterpreted Psalm 1 (and other promises like it) to be about a future event since it does not seem to be fulfilled in the current age.
Can we know if the idea of a final judgement was embedded in Psalm 1?