FX.115 CadCraft: long block list ran off the screen; INSERT gave no near names; FILLET radius prompt did not say clicks measure it

From four asks in one message. The block list in the side panel now scrolls inside its panel (max 24 rem / 45% of the window). INSERT: a name that is no block lists the blocks that start with or hold what was typed ("Did you mean"), and a name that is a block while others start the same way ("1" and "10", "12") says so. FILLET: the radius prompt says a value is typed or two clicks measure it (it already did). Already there and answered: UCS (UCS command), STRETCH by crossing window (select with C or drag right to left). Not built: a dropdown of candidates under the command line. Checked by reading + syntax; browser-aids.mjs covers the other fixes only.