Preheat the oven to 160°C (320°F) or 140°C fan, and place a rack in the middle of the oven.
Line the bottom of a 20 cm (8 inch) springform pan by inverting the base, lightly buttering it, pressing on parchment paper, and clipping it into place so the paper sticks out, then butter and line the sides as well.
Crush the biscuits into fine crumbs in a food processor or with a rolling pin, mix in the melted butter until the texture is like wet sand, then press firmly into the base and up the sides of the pan using a flat-bottomed cup.
Beat the softened cream cheese with an electric mixer on medium speed until smooth but not airy, add the flour and mix briefly, then add vanilla, yogurt, sugar, and lemon zest, mixing until just combined.
Add the eggs one at a time, mixing gently after each until smooth, then fold in the blueberries with a spatula and pour the filling into the prepared crust.
Bake the cheesecake for about 70 minutes until the top is pale golden, slightly puffed, and only jiggles gently when the pan is shaken, then turn off the oven, crack the door open about 20 cm, and let the cheesecake cool inside for 2 hours.
Refrigerate the cheesecake in the pan for at least 4 hours or overnight, then release the springform sides and carefully slide the cheesecake onto a serving plate.
For the topping, simmer 125 g of the blueberries with sugar, lemon juice, and vanilla in a saucepan for 7 minutes until the berries break down, stir in the cornstarch-water slurry to thicken, then add the remaining blueberries and let the sauce cool to a syrupy consistency.
Spread the blueberry topping evenly over the chilled cheesecake, refrigerate for at least 2 more hours, then slice and serve.