QA: scan the Enzyme and Mooncake extensions

[ChrisRackauckas-Claude]

Please ignore this PR until it has been reviewed by @ChrisRackauckas.

What this fixes

run_qa runs ExplicitImports' checks over the package module and its submodules.
ExplicitImports does know about extensions — it reads the [extensions] table
out of Project.toml — but it skips any extension for which
Base.get_extension(mod, ext) returns nothing, and an extension module only
exists once its triggers are loaded. The QA environment loaded no weakdeps, so
neither FunctionWrappersWrappersEnzymeExt nor
FunctionWrappersWrappersMooncakeExt was being checked at all.

Adding Enzyme, EnzymeCore and Mooncake to test/qa/Project.toml (compat
mirroring the root Project.toml) and using them in test/qa/qa.jl puts both
extensions under QA.

Coverage

• Now scanned: FunctionWrappersWrappersEnzymeExt, FunctionWrappersWrappersMooncakeExt.
• Left out: nothing. All three weakdeps are pure-Julia and resolve in the QA
  environment, so there are no remaining unscanned extensions.

Fixed at the source (not ignored)

no_implicit_imports flagged the Enzyme extension for relying on using Enzyme
/ using EnzymeCore / using EnzymeCore.EnzymeRules and then referring to
Enzyme, EnzymeCore, EnzymeRules, Const, Duplicated, BatchDuplicated,
Forward, ForwardWithPrimal. Those became explicit imports:

using Enzyme: Enzyme
using EnzymeCore: EnzymeCore, BatchDuplicated, Const, Duplicated, Forward, ForwardWithPrimal
using EnzymeCore.EnzymeRules: EnzymeRules

EnzymeRules is imported from the submodule that owns it rather than from
EnzymeCore (which does not export it), and the three inactive_type
definitions now go through EnzymeRules.inactive_type instead of the
EnzymeCore.EnzymeRules.inactive_type path. Side benefit: this removes the two

WARNING: both EnzymeRules and Enzyme export "runtime_activity"; uses of it in module FunctionWrappersWrappersEnzymeExt must be qualified
WARNING: both EnzymeRules and Enzyme export "tape_type"; ...

warnings that were printed every time the extension loaded.

The Mooncake extension needed no source changes.

Ignore entries added

All of these are AD rule-authoring interfaces: the names a package must use to
teach an AD backend about a new callable, which the backend documents but has not
declared public. There is no public spelling for any of them.

all_qualified_accesses_are_public:

Symbol	Owner	Why unavoidable
forward, augmented_primal, reverse, inactive_type, strong_zero	EnzymeCore.EnzymeRules	The generic functions a rule author adds methods to. EnzymeRules exports the config accessors (needs_primal, overwritten, runtime_activity, ...) but not these extension points.
build_rrule, rrule!!, tangent_type, primal	Mooncake	Mooncake declares only its top-level entry points public (value_and_gradient!!, prepare_gradient_cache, Config, Dual, ...); the entire rule API is documented-but-not-public.
Typeof	Core	Standard idiom for building a call-signature tuple type; typeof is wrong for arguments that are themselves types, and there is no Base equivalent.

all_explicit_imports_are_public: @is_primitive, CoDual, MinimalCtx,
NoRData, NoTangent, fdata, zero_tangent — same Mooncake rule API as above.

The pre-existing :FunctionWrapper ignore is unchanged. No check was disabled and
nothing was marked broken.

Local runs

QA on the LTS (Julia 1.10.11) — the two public-API checks are skipped there by
SciMLTesting:

Test Summary: | Pass  Total     Time
QA            |   18     18  1m01.3s
     Testing FunctionWrappersWrappers tests passed

QA on Julia 1.12.6, where all_qualified_accesses_are_public and
all_explicit_imports_are_public also run:

Test Summary: | Pass  Total     Time
QA            |   20     20  3m40.6s
     Testing FunctionWrappersWrappers tests passed

Because the Enzyme extension's source changed, both AD groups were re-run on 1.10:

Test Summary: | Pass  Total   Time
Enzyme        |   68     68  35.1s
     Testing FunctionWrappersWrappers tests passed

Test Summary: | Pass  Total   Time
Mooncake      |   13     13  10.3s
     Testing FunctionWrappersWrappers tests passed

Runic 1.7.0 reports the touched files clean. No Manifest.toml is committed.