Fix test failures in the coverage tests

- unit-custom-object-key-type: remove the unused make_strict_key(strict_key)
  overload, the unused range constructor and default constructor, and guard
  data() with JSON_DIAGNOSTICS (unused-function/-member-function errors with
  GCC and clang -Weverything).
- unit-json_view_compare: move the two new sections to the new
  unit-json_view_compare_values.cpp, as the object file got too large for the
  MinGW assembler again, and use a std::map with std::greater instead of
  std::unordered_map, which does not accept the incomplete basic_json
  (clang 3.9, icpc).
- unit-json_view_dump: rename the variables that hid outer ones (MSVC C4456).
- unit-stream-bulk-scan: restore the real size of the oversized get area
  before the adapter is destroyed (JSON_PRECISE_STREAM_POSITION reads the
  character at the read position), and skip the test where the streambuf
  cannot hold a get area larger than an int (MSVC).
- unit-regression1: with JSON_NO_THREAD_LOCAL, copies are built member by
  member and keep correct timestamps, so check the corresponding outcome.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N5NasAgbDGG28MqXjQvLqp
Signed-off-by: Claude <noreply@anthropic.com>

tests/src/unit-json_view_dump.cpp

@@ -247,15 +247,15 @@ TEST_CASE("json_view dump")
                     })
             {
                 CAPTURE(token)
-                const std::string text = std::string("[") + token + padding + "]";
-                const json_document d = json_document::parse(text);
-                const json j = json::parse(text);
-                CHECK(d.root()[0].get<double>() == j[0].get<double>());
-                CHECK(d.root().dump() == j.dump());
+                const std::string padded = std::string("[") + token + padding + "]";
+                const json_document padded_document = json_document::parse(padded);
+                const json padded_json = json::parse(padded);
+                CHECK(padded_document.root()[0].get<double>() == padded_json[0].get<double>());
+                CHECK(padded_document.root().dump() == padded_json.dump());
                 // a float document converts the tokens as well
                 using json_float = nlohmann::basic_json<std::map, std::vector, std::string, bool, std::int64_t, std::uint64_t, float>;
-                const nlohmann::basic_json_document<json_float> float_doc = nlohmann::basic_json_document<json_float>::parse(text);
-                CHECK(float_doc.root()[0].get<float>() == json_float::parse(text)[0].get<float>());
+                const nlohmann::basic_json_document<json_float> float_doc = nlohmann::basic_json_document<json_float>::parse(padded);
+                CHECK(float_doc.root()[0].get<float>() == json_float::parse(padded)[0].get<float>());
             }
         }