chore: organize solution into module folders (Core/Server/Drivers/Client/Tooling)

Group all 69 projects into category subfolders under src/ and tests/ so the
Rider Solution Explorer mirrors the module structure. Folders: Core, Server,
Drivers (with a nested Driver CLIs subfolder), Client, Tooling.

- Move every project folder on disk with git mv (history preserved as renames).
- Recompute relative paths in 57 .csproj files: cross-category ProjectReferences,
  the lib/ HintPath+None refs in Driver.Historian.Wonderware, and the external
  mxaccessgw refs in Driver.Galaxy and its test project.
- Rebuild ZB.MOM.WW.OtOpcUa.slnx with nested solution folders.
- Re-prefix project paths in functional scripts (e2e, compliance, smoke SQL,
  integration, install).

Build green (0 errors); unit tests pass. Docs left for a separate pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/Server/ZB.MOM.WW.OtOpcUa.Admin/Components/Layout/MainLayout.razor

@@ -0,0 +1,38 @@
+@inherits LayoutComponentBase
+
+<div class="d-flex" style="min-height: 100vh;">
+    <nav class="bg-dark text-light p-3" style="width: 220px;">
+        <h5 class="mb-4">OtOpcUa Admin</h5>
+        <ul class="nav flex-column">
+            <li class="nav-item"><a class="nav-link text-light" href="/">Overview</a></li>
+            <li class="nav-item"><a class="nav-link text-light" href="/fleet">Fleet status</a></li>
+            <li class="nav-item"><a class="nav-link text-light" href="/hosts">Host status</a></li>
+            <li class="nav-item"><a class="nav-link text-light" href="/clusters">Clusters</a></li>
+            <li class="nav-item"><a class="nav-link text-light" href="/reservations">Reservations</a></li>
+            <li class="nav-item"><a class="nav-link text-light" href="/certificates">Certificates</a></li>
+            <li class="nav-item"><a class="nav-link text-light" href="/role-grants">Role grants</a></li>
+        </ul>
+
+        <div class="mt-5">
+            <AuthorizeView>
+                <Authorized>
+                    <div class="small text-light">
+                        Signed in as <a class="text-light" href="/account"><strong>@context.User.Identity?.Name</strong></a>
+                    </div>
+                    <div class="small text-muted">
+                        @string.Join(", ", context.User.Claims.Where(c => c.Type.EndsWith("/role")).Select(c => c.Value))
+                    </div>
+                    <form method="post" action="/auth/logout">
+                        <button class="btn btn-sm btn-outline-light mt-2" type="submit">Sign out</button>
+                    </form>
+                </Authorized>
+                <NotAuthorized>
+                    <a class="btn btn-sm btn-outline-light" href="/login">Sign in</a>
+                </NotAuthorized>
+            </AuthorizeView>
+        </div>
+    </nav>
+    <main class="flex-grow-1 p-4">
+        @Body
+    </main>
+</div>