test: specs and ProjectDependency() in a project file's static initialisers

ProjectArgs gets a sibling that makes its own sibling's spec at
namespace scope. Before the fix that spec took the args the file was
first loaded with; now it takes none on every load. The checks go
through one CheckLoaded helper, which prints what each sibling was
given, so a failure says which args a wrong frame handed over.

ProjectDependency loads a fixture whose static initialiser asks for its
pragma dependency, in a child, because a throw there terminates the
process: before the fix it found none. The check that the dependency
gets none of the consumer's args moves into the first load, which now
passes the app an arg it ignores; the separate load could not fail its
own check, and its early return skipped every later one.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/ProjectArgs/fixture/static/project.cpp

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: LGPL-3.0-only
+// SPDX-FileCopyrightText: Copyright (C) 2026 Catcrafts®
+
+import std;
+import Crafter.Build;
+using namespace Crafter;
+
+// Makes its sibling's spec at namespace scope, so the spec's args default
+// while LoadProject dlopens this file: before CrafterBuildProject is called,
+// and on the first load of the file only.
+namespace {
+    const LocalProjectSpec LeafSpec{ .projectFile = "../leaf/project.cpp" };
+}
+
+extern "C" Configuration CrafterBuildProject(std::span<const std::string_view> args) {
+    Configuration* leaf = LocalProject(LeafSpec);
+
+    Configuration cfg;
+    cfg.path = "./";
+    cfg.name = "static";
+    cfg.outputName = "static";
+    cfg.type = ConfigurationType::LibraryStatic;
+    ApplyStandardArgs(cfg, args);
+    cfg.dependencies = { leaf };
+    return cfg;
+}