Add builtin functions for destroy, with special requirements in facet types (#6035)

This is in support of a goal of changing the blanket `destroy` impl to
use (roughly):

```
private fn CanAggregateDestroy() -> type = "type.can_aggregate_destroy";

// Handles aggregate type destruction.
impl forall [AggregateDestroyT:! CanAggregateDestroy()] AggregateDestroyT as Destroy {
  fn Op[addr self: Self*]() = "type.aggregate_destroy";
}
```

That isn't done here because there's still other issues that migrating
raises. What this *does* do is add the builtin functions, and in
particular, support to `FacetTypeInfo` to make `CanAggregateDestroy`
work.

The "special requirement" approach in `FacetTypeInfo` allows us to
support restricting a blanket impl under the current approach of impls.
Maybe we'll find a cleaner approach that can work in the future, but
this fits into the current model by propagating similar to other
requirements. I'm using an enum mask because we have a number of similar
things to add (e.g. copy, move) but I'm not sure we need a full vector.

A few alternatives considered were:

- Supporting syntax more like `where .Self impls
TypeCanAggregateDestroy(.Self, SupportedInterface,
UnsupportedInterface)`. I think it'd be a little cleaner, but requires
better compile-time evaluation in order to assess the type of the call.
Right now it's expected to be a `FacetType` too early to make this work,
and I was concerned about pouring too much more time down this route.
- Providing an actual interface, in particular doing name lookup back
into `Core.` for an interface. This would've added name lookup overhead,
and the question of whether an `impl` exists.
- Generating an interface. This avoids the name lookup, but would still
raise the question of whether an `impl` should also be generated. Work
I've previously done generating interfaces for class destruction also
feels complex to both write and understand (an unfortunate issue).
- Still modeling as an `ImplsConstraint`, for example by defining a
special `InterfaceId::CanAggregateDestroy = -2` similar to what we do on
other ids. I was hesitant because of how this expands the number of
modes of `InterfaceId`, and things for consuming code to watch out for,
for what feels like a relatively niche set of use-cases that are only
interface-like.

---------

Co-authored-by: Dana Jansens <danakj@orodu.net>

toolchain/check/testdata/interop/cpp/enum/anonymous.carbon

@@ -70,12 +70,12 @@ fn G() {
 // CHECK:STDOUT:   %ptr.73d: type = ptr_type %.bb7 [concrete]
 // CHECK:STDOUT:   %F__carbon_thunk.type.eda1ac.2: type = fn_type @F__carbon_thunk.2 [concrete]
 // CHECK:STDOUT:   %F__carbon_thunk.0cd6a8.2: %F__carbon_thunk.type.eda1ac.2 = struct_value () [concrete]
-// CHECK:STDOUT:   %T.as.Destroy.impl.Op.type.bf8: type = fn_type @T.as.Destroy.impl.Op, @T.as.Destroy.impl(%.bb7) [concrete]
-// CHECK:STDOUT:   %T.as.Destroy.impl.Op.823: %T.as.Destroy.impl.Op.type.bf8 = struct_value () [concrete]
-// CHECK:STDOUT:   %T.as.Destroy.impl.Op.type.140: type = fn_type @T.as.Destroy.impl.Op, @T.as.Destroy.impl(%C) [concrete]
-// CHECK:STDOUT:   %T.as.Destroy.impl.Op.d4e: %T.as.Destroy.impl.Op.type.140 = struct_value () [concrete]
-// CHECK:STDOUT:   %T.as.Destroy.impl.Op.type.a23: type = fn_type @T.as.Destroy.impl.Op, @T.as.Destroy.impl(%.4f0) [concrete]
-// CHECK:STDOUT:   %T.as.Destroy.impl.Op.8db: %T.as.Destroy.impl.Op.type.a23 = struct_value () [concrete]
+// CHECK:STDOUT:   %T.as.Destroy.impl.Op.type.39a: type = fn_type @T.as.Destroy.impl.Op, @T.as.Destroy.impl(%.bb7) [concrete]
+// CHECK:STDOUT:   %T.as.Destroy.impl.Op.bd3: %T.as.Destroy.impl.Op.type.39a = struct_value () [concrete]
+// CHECK:STDOUT:   %T.as.Destroy.impl.Op.type.37e: type = fn_type @T.as.Destroy.impl.Op, @T.as.Destroy.impl(%C) [concrete]
+// CHECK:STDOUT:   %T.as.Destroy.impl.Op.a28: %T.as.Destroy.impl.Op.type.37e = struct_value () [concrete]
+// CHECK:STDOUT:   %T.as.Destroy.impl.Op.type.088: type = fn_type @T.as.Destroy.impl.Op, @T.as.Destroy.impl(%.4f0) [concrete]
+// CHECK:STDOUT:   %T.as.Destroy.impl.Op.dda: %T.as.Destroy.impl.Op.type.088 = struct_value () [concrete]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
@@ -139,17 +139,17 @@ fn G() {
 // CHECK:STDOUT:   %.loc15_20.2: ref %.bb7 = temporary %.loc15_20.1, %e.ref
 // CHECK:STDOUT:   %addr.loc15_22: %ptr.73d = addr_of %.loc15_20.2
 // CHECK:STDOUT:   %F__carbon_thunk.call.loc15: init %empty_tuple.type = call imports.%F__carbon_thunk.decl.e1b8ec.2(<error>, %addr.loc15_22)
-// CHECK:STDOUT:   %T.as.Destroy.impl.Op.bound.loc15_20: <bound method> = bound_method %.loc15_20.2, constants.%T.as.Destroy.impl.Op.823
+// CHECK:STDOUT:   %T.as.Destroy.impl.Op.bound.loc15_20: <bound method> = bound_method %.loc15_20.2, constants.%T.as.Destroy.impl.Op.bd3
 // CHECK:STDOUT:   <elided>
 // CHECK:STDOUT:   %bound_method.loc15_20: <bound method> = bound_method %.loc15_20.2, %T.as.Destroy.impl.Op.specific_fn.1
 // CHECK:STDOUT:   %addr.loc15_20: %ptr.73d = addr_of %.loc15_20.2
 // CHECK:STDOUT:   %T.as.Destroy.impl.Op.call.loc15_20: init %empty_tuple.type = call %bound_method.loc15_20(%addr.loc15_20)
-// CHECK:STDOUT:   %T.as.Destroy.impl.Op.bound.loc15_11: <bound method> = bound_method %.loc15_11.3, constants.%T.as.Destroy.impl.Op.d4e
+// CHECK:STDOUT:   %T.as.Destroy.impl.Op.bound.loc15_11: <bound method> = bound_method %.loc15_11.3, constants.%T.as.Destroy.impl.Op.a28
 // CHECK:STDOUT:   <elided>
 // CHECK:STDOUT:   %bound_method.loc15_11: <bound method> = bound_method %.loc15_11.3, %T.as.Destroy.impl.Op.specific_fn.2
 // CHECK:STDOUT:   %addr.loc15_11.2: %ptr.d9e = addr_of %.loc15_11.3
 // CHECK:STDOUT:   %T.as.Destroy.impl.Op.call.loc15_11: init %empty_tuple.type = call %bound_method.loc15_11(%addr.loc15_11.2)
-// CHECK:STDOUT:   %T.as.Destroy.impl.Op.bound.loc8: <bound method> = bound_method %.loc8_12.2, constants.%T.as.Destroy.impl.Op.8db
+// CHECK:STDOUT:   %T.as.Destroy.impl.Op.bound.loc8: <bound method> = bound_method %.loc8_12.2, constants.%T.as.Destroy.impl.Op.dda
 // CHECK:STDOUT:   <elided>
 // CHECK:STDOUT:   %bound_method.loc8: <bound method> = bound_method %.loc8_12.2, %T.as.Destroy.impl.Op.specific_fn.3
 // CHECK:STDOUT:   %addr.loc8_12: %ptr.793 = addr_of %.loc8_12.2