fix: printf format, paths WSL actualizados y repo_url en app.md

Corrige fprintf que usaba %s con std::string sin .c_str().
Actualiza path WSL en el launcher PowerShell a Ubuntu-22.04.
Añade repo_url en app.md apuntando al repo en Gitea.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app.md

@@ -18,7 +18,7 @@ uses_types: []
 framework: "imgui"
 entry_point: "main.cpp"
 dir_path: "apps/registry_dashboard"
-repo_url: ""
+repo_url: "https://gitea-dgg044oo04woo4ggcsws4gk0.organic-machine.com/dataforge/registry_dashboard"
 ---
 
 ## Arquitectura

main.cpp

@@ -61,7 +61,7 @@ int main(int argc, char** argv) {
             fprintf(stdout, "Using: %s\n", g_db_path.c_str());
             break;
         }
-        fprintf(stderr, "Not found: %s\n", candidate);
+        fprintf(stderr, "Not found: %s\n", candidate.c_str());
     }
 
     if (g_db_path.empty()) {

registry_dashboard.ps1

@@ -1,6 +1,5 @@
 $exe = Join-Path $PSScriptRoot "registry_dashboard.exe"
 
 & $exe `
-    "\\wsl.localhost\Ubuntu\home\lucas\fn_registry\registry.db" `
-    "\\wsl$\Ubuntu\home\lucas\fn_registry\registry.db" `
-    "$PSScriptRoot\registry.db"
+    "\\wsl.localhost\Ubuntu-22.04\home\lucas\fn_registry\registry.db" `
+