Checkpoint the party/runtime stack before share-program and malicious-mode work.

Ship the TLS mesh, composer, Beaver/Yao/leaf MPC, prep/online paths, apps, and docs so the tree is pushable before elevating share_expr, security_mode, and prep resume.

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

examples/applications/it_pir3.cpp

@@ -0,0 +1,49 @@
+#include <cstdint>
+#include <iostream>
+#include <vector>
+
+#include "dpf.hpp"
+#include "dpf/app_flow.hpp"
+#include "dpf/app_plans.hpp"
+
+// Three-server index PIR with the information-theoretic DPF
+// (ePrint 2023/028). The database is public and replicated. Each server
+// dots its additive share with the table; the three dots sum to the record.
+// make_dpf3 remains the computational (2,3) Shamir key.
+//
+//   c++ -std=c++17 -march=native -I include -I thirdparty \
+//       examples/applications/it_pir3.cpp
+
+int main()
+{
+    constexpr std::size_t n = 256;
+    constexpr std::uint8_t index = 42;
+
+    std::vector<std::uint64_t> database(n);
+    for (std::size_t i = 0; i < n; ++i)
+        database[i] = i * i + 1;
+
+    auto [k0, k1, k2] = dpf::make_it_dpf3(index, 1);
+    const auto s0 = dpf::eval_it_dpf3_inner_product(k0, database);
+    const auto s1 = dpf::eval_it_dpf3_inner_product(k1, database);
+    const auto s2 = dpf::eval_it_dpf3_inner_product(k2, database);
+    const auto opened = s0 + s1 + s2;
+    if (opened != database[index])
+    {
+        std::cerr << "it_pir3\n";
+        return 1;
+    }
+
+    {
+        constexpr std::size_t query_bytes =
+            dpf::it_dpf3_key::domain_size * sizeof(std::uint64_t);
+        if (int rc = dpf::app::run_measured("it_pir3",
+                dpf::protocol::n_server_pir_plan(0, 3, query_bytes,
+                    sizeof(std::uint64_t)),
+                2))
+            return rc;
+    }
+
+    std::cout << opened << "\n";
+    return 0;
+}