Upgrade the vendored nlohmann JSON to 3.12.0 and build the docs with Doxygen 1.15.

Co-authored-by: Cursor <cursoragent@cursor.com>

include/dpf/eval_interval.hpp

@@ -193,7 +193,6 @@ void store_interval_leaf(OutputBuffer && outbuf, std::size_t k, const LeafT & le
 /// @param to_node the `to_node`
 /// @param outbufs the named output buffers
 /// @param memoizer the memoizer built for this key
-/// @param IIs the `IIs`
 /// @param start the start of the range
 /// @throws std::runtime_error if `to_node<from_node`
 template <std::size_t ...Is,

include/dpf/eval_unified.hpp

@@ -663,7 +663,6 @@ auto eval_sequence_breadth_first(out_t<I, N>, const KeyT & key,
 /// @tparam KeyT key type
 /// @tparam ForwardIterator forward iterator type
 /// @tparam KeyT key type
-/// @param N the `N`
 /// @param key the `key`
 /// @param begin the iterator to the first query
 /// @param end the iterator past the last query

include/dpf/fp61.hpp

@@ -1,5 +1,5 @@
 /// @file dpf/fp61.hpp
-/// @brief Prime field \(\mathbb{F}_{2^{61}-1}\) additive output type.
+/// @brief Prime field of order `2^61 - 1`, as an additive output type.
 /// @copyright Copyright (c) 2019-2026 Ryan Henry and [others](@ref authors)
 /// @license Released under a GNU General Public v2.0 (GPLv2) license;
 ///          see [LICENSE.md](@ref license) for details.
@@ -24,7 +24,7 @@ namespace dpf
 /// @brief Modulus \(p = 2^{61}-1\). `p` itself reduces to 0.
 inline constexpr std::uint64_t fp61_mod = (std::uint64_t{1} << 61) - 1;
 
-/// @brief Additive element of \(\mathbb{F}_{2^{61}-1}\).
+/// @brief Additive element of the field of order `2^61 - 1`.
 class fp61
 {
   public:

include/dpf/verifiable.hpp

@@ -3,7 +3,7 @@
 /// @details VDPF proof fold follows de Castro–Polychroniadou (hash-based
 ///          correction seeds, 2λ-bit tokens, equality Verify). Extractable
 ///          checks are public-part equality, ROM-style leaf XOF, and an
-///          \(\mathbb{F}_{2^{61}-1}\) weight-1 subset sketch. Phantom tags
+///          field of order `2^61 - 1` weight-1 subset sketch. Phantom tags
 ///          `dpf::verifiable` / `dpf::extractable` live in placement.hpp.
 /// @copyright Copyright (c) 2019-2026 Ryan Henry and [others](@ref authors)
 /// @license Released under a GNU General Public v2.0 (GPLv2) license;