[M5+] wire resolver::discover into cargoxx add

src/linkdb/curated.cpp

@@ -71,16 +71,6 @@ auto load_curated(const std::filesystem::path& path)
     return out;
 }
 
-auto default_overlay_path() -> std::filesystem::path {
-    namespace fs = std::filesystem;
-    if (auto* xdg = std::getenv("XDG_CACHE_HOME"); xdg && *xdg) {
-        return fs::path{xdg} / "cargoxx" / "linkdb.sqlite";
-    }
-    if (auto* home = std::getenv("HOME"); home && *home) {
-        return fs::path{home} / ".cache" / "cargoxx" / "linkdb.sqlite";
-    }
-    return fs::current_path() / ".cargoxx-linkdb.sqlite";
-}
 
 auto resolve_curated(const std::map<std::string, std::vector<detail::CuratedRecipe>>& curated,
                      const std::string& package, const std::string& version,
@@ -136,6 +126,17 @@ auto resolve_curated(const std::map<std::string, std::vector<detail::CuratedReci
 
 } // namespace
 
+auto default_overlay_path() -> std::filesystem::path {
+    namespace fs = std::filesystem;
+    if (auto* xdg = std::getenv("XDG_CACHE_HOME"); xdg && *xdg) {
+        return fs::path{xdg} / "cargoxx" / "linkdb.sqlite";
+    }
+    if (auto* home = std::getenv("HOME"); home && *home) {
+        return fs::path{home} / ".cache" / "cargoxx" / "linkdb.sqlite";
+    }
+    return fs::current_path() / ".cargoxx-linkdb.sqlite";
+}
+
 auto Database::open(std::optional<std::filesystem::path> overlay_path) -> util::Result<Database> {
     Database db;
 

src/linkdb/linkdb.cppm

@@ -131,6 +131,12 @@ class Database {
     std::unique_ptr<detail::OverlayState> overlay_;
 };
 
+// Returns the default overlay-database path:
+//   $XDG_CACHE_HOME/cargoxx/linkdb.sqlite   (if XDG_CACHE_HOME is set)
+//   $HOME/.cache/cargoxx/linkdb.sqlite       (else if HOME is set)
+//   <cwd>/.cargoxx-linkdb.sqlite             (final fallback)
+auto default_overlay_path() -> std::filesystem::path;
+
 // Pure helpers exported for unit testing.
 auto substitute_components(std::string find_package, const std::vector<std::string>& components)
     -> std::string;

src/linkdb/overlay.cpp

@@ -267,6 +267,14 @@ auto overlay_is_fresh(const OverlayRow& row, std::int64_t now) -> bool {
     if (row.source == "manual" || row.source == "curated") {
         return true;
     }
+    // verified_at == 0 marks a provisional row — written by
+    // resolver::verify_link before its build runs and either confirmed
+    // (verified_at = now) or deleted afterwards. The verifying build
+    // itself must see this row to surface the candidate recipe to its
+    // codegen step.
+    if (row.verified_at == 0) {
+        return true;
+    }
     return (now - row.verified_at) < THIRTY_DAYS_SECONDS;
 }