feat: implement MoloApp plans 01-15 with integration

Full C++23 framework tree: runtime, observability, security,
data, app, realtime, supervisor, clients, CLI, example plus
enterprise tenancy, audit, operability, governance,
supplychain. Postgres via docker compose for tests.

example/fw/Negotiate.cpp

@@ -0,0 +1,70 @@
+#include "Negotiate.hpp"
+
+#include <cctype>
+
+namespace molo::example::fw {
+
+namespace {
+
+std::string trim(std::string s) {
+  while (!s.empty() && (s.front() == ' ' || s.front() == '\t')) s.erase(s.begin());
+  while (!s.empty() && (s.back() == ' ' || s.back() == '\t')) s.pop_back();
+  return s;
+}
+
+}  // namespace
+
+std::string negotiate(const std::string& accept,
+                      const std::vector<std::string>& available) {
+  if (available.empty()) throw HttpError(500, "no_offers", "no offers");
+  if (accept.empty()) return available.front();
+  struct Range {
+    std::string type;
+    double q = 1.0;
+  };
+  std::vector<Range> ranges;
+  std::size_t start = 0;
+  while (start < accept.size()) {
+    std::size_t comma = accept.find(',', start);
+    if (comma == std::string::npos) comma = accept.size();
+    std::string part = trim(accept.substr(start, comma - start));
+    std::size_t semi = part.find(';');
+    Range r{trim(part.substr(0, semi)), 1.0};
+    if (semi != std::string::npos) {
+      std::string params = part.substr(semi + 1);
+      std::size_t q = params.find("q=");
+      if (q != std::string::npos) {
+        try {
+          r.q = std::stod(params.substr(q + 2));
+        } catch (...) {
+          r.q = 1.0;
+        }
+      }
+    }
+    ranges.push_back(r);
+    start = comma + 1;
+  }
+  std::string best;
+  double best_q = -1.0;
+  for (const auto& a : available) {
+    for (const auto& r : ranges) {
+      bool hit = r.type == "*/*" || r.type == a;
+      if (!hit) {
+        std::size_t slash = a.find('/');
+        std::string wild = slash == std::string::npos
+                               ? "*/*"
+                               : a.substr(0, slash) + "/*";
+        hit = r.type == wild;
+      }
+      if (hit && r.q > best_q) {
+        best_q = r.q;
+        best = a;
+      }
+    }
+  }
+  if (best.empty() || best_q <= 0.0)
+    throw HttpError(406, "not_acceptable", "no acceptable format");
+  return best;
+}
+
+}  // namespace molo::example::fw