Thinking about this thread from a little way down the page, I had a few ideas:-

1) Now that we know that the leading edge is particularly vulnerable and a particularly crucial (I klnow we knew most of that already, but we know even more now): The leading edge is a simple geometry. It looks like every leading edge RCC element is identical, so a sleeve to go on the outside of any damaged section would be easy to design and carry. Attachment would require either a good vacuum-setting glue or titanium rivets/screws. The tricky area becomes the point where the wing angle changes. You might need to carry a special shaped element for this section. (and a left and right handed one, too! - the normal wing sleeves would be 'ambidextrous'))

2) Flat surfaces of the wing or body can have a flat repair plate with ceramic tiles or RCC or even solid titanium. Whatever, the plate should feather out to the edge and have a prong in the centre base to go through any hole. (or better, a set of pre-machined screw threads, and a variety of prongs, grabs, bolts, etc to fit as required.

3) Curved areas of the wing and body are, of course, the most difficult. I recall my visit to the Buran, which was deliberately box-like to make as many flats and as few vurves as possible. The big problem with heat resistant materials is that they are either brittle (ceramic) or tough (titanium) and don't bend readily. I suspect that with ingenuity something like those 1970's mosaic tile wallpares can be produced. (For those too young to remember, there was a fashion for tiles an inch across or smaller, that were mounted on hessian backing. The whole thing came on a roll, and you cut to size, glued to the wall, and filled the gaps with grout. Instant regular mini tiles)

So for the shuttle, I envisage some flexible sheets of backing material, densely covered with foam tiles. The sheet would be unrolled over the area of damage and fixed by screws etc through the backing sheet. then a heat-resistant grout would be smoothed over the curved sheet to fill the gracks/gaps where it took a curve.

Problems with the above:

All the above assumes that the Shuttle is built like a house or a boat i.e. it either has a solid frame and surface that you can drill screws and rivet holes into wherever you like and can rely on them to hold firmly, or it has a strong surface and frame elements that you can pierce and lock onto with toggle clamps etc.

It may be that a redesign and total rebuild is required before a repair kit becomes possible. You might need every single one of the existing tiles to have a recessed threaded hole in the centre, covered by a heat resistant plug, and in operation one would drill-out the plug and clean the thread then insert a fixing bolt into it. Hours of work, even on Earth, to install such a patch! You might get away with "most" tiles having such attachment points, or having the tapped holes in the underlying structure, at the places where tiles join, so you just drill-out the joint. The weight penalty would be noticeable!

Also, a space setting glue, and a space-setting heat resistant paste are required. I have no idea if these are possible.

All the above makes it likely that such a complex and complete kit would be stored on the ISS, not as a 'spare tyre' on the Shuttle itself. Each flight the first job on arrival is to check for damage, then begin the repair work if needed. Only when the return bus was ready could you get on with the 'normal' jobs for that tour.

Finally:

it would be great if one had heat-resistant Duct tape. All you would need would be enough layers of that, interlayered with stiff flexible sheets to give form and stability. With such a system, you wouldn't need the ISS as a repair base and spare tyre depot!