The examples call `engine::realize_gram`, which now includes a call to
`symmetric_kernel`, so we need to make sure that `symmetric_kernel`
can run on whatever target Cargo uses for examples. For that target on
my machine, `console::log_1` panics with the message "function not
implemented on non-`wasm32` targets".
This seems like a good starting point, even though the code is messy and
the deformation routine has some numerical quirks. Note that the translation
direction is mixed up: the keys are for x, but the velocity field is for z.
Turn on the browser console panic message output provided by the
`console_error_panic_hook` feature. This feature was already enabled by
default in our Cargo configuration, but it wasn't actually being used.
At the end of the realization routine, use the computed Hessian to find
the tangent space of the solution variety, and return it alongside the
realization. Since altering the constraints can change the tangent space
without changing the solution, we compute the tangent space even when
the guess passed to the realization routine is already a solution.
