Refine .asm component extraction: batch DB queries, wider suffix regex, placement check

- Batch the DB lookup per file instead of per code in scripts/ExtractCreoStrings.cs:
  files_ultima_versione is an unmaterialized view, so each query rescanned the whole
  files table (~230ms) - batching cuts a multi-minute BFS to seconds.
- Widen the code regex to accept a revision letter and a "_..." suffix together
  (e.g. "9284200366A_C01"), and purely numeric "_NNNN" suffixes (e.g. dimensional
  variants like "2702220182_8188"), not just letter+digits.
- Require bare digit-only candidates to also appear inside a real
  "Componente ID N (...)"/"Component id N (...)" placement, filtering out
  incidental references to a containing assembly's own code.
- scripts/ExtractCreoStrings.cs now reports only the direct references of the given
  .asm (one level, matching Creo's own tree for that file) instead of recursing into
  sub-assemblies.
- Port the regex and placement-check refinements to the production
  AssemblyComponentScanner.cs used by the app's "Trova componenti referenziati" and
  "Verifica completezza" phases.
- Document the new false-positive categories (parent/container self-reference,
  suppressed/removed components with residual placement, placement missing
  suffix/bracket detail) in docs/formato-asm.md, generalized beyond the specific
  assemblies used to find them.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

CadSearchGui.Tests/AssemblyComponentScannerTests.cs

@@ -14,8 +14,10 @@ public class AssemblyComponentScannerTests
     [Fact]
     public void Scarta_codici_con_una_sola_occorrenza()
     {
-        // "11112222" compare 2 volte (riferimento vero), "99998888" una sola (rumore).
-        string percorso = ScriviAsmFinto("blah 11112222 blah 99998888 blah 11112222 fine");
+        // "11112222" compare 2 volte con un vero placement (riferimento vero), "99998888"
+        // una sola volta senza placement (rumore).
+        string percorso = ScriviAsmFinto(
+            "blah Componente ID 1 (11112222.PRT) blah 99998888 blah 11112222 fine");
         try
         {
             var codici = AssemblyComponentScanner.EstraiCodiciReferenziati(percorso);
@@ -25,6 +27,20 @@ public class AssemblyComponentScannerTests
         finally { File.Delete(percorso); }
     }
 
+    [Fact]
+    public void Scarta_codice_ripetuto_senza_un_vero_placement()
+    {
+        // Riferimento al nome di un altro assieme (es. il padre che lo contiene): ripetuto
+        // più volte ma mai dentro un placement "Componente ID N (...)" - va scartato.
+        string percorso = ScriviAsmFinto("padre 33334444 assieme 33334444_D200 33334444");
+        try
+        {
+            var codici = AssemblyComponentScanner.EstraiCodiciReferenziati(percorso);
+            Assert.DoesNotContain("33334444", codici);
+        }
+        finally { File.Delete(percorso); }
+    }
+
     [Fact]
     public void Riconosce_sotto_assiemi_con_suffisso_stile_D100()
     {