feat(registratura): fix thread clear, close via conex entry

- Fix threadParentId clear: always show "Sterge" button even when parent not found in allEntries
- Bigger clear button with text label instead of tiny X icon
- Fallback display when parent not in current list (shows truncated ID)
- Close via conex: table/detail "Inchide" now creates a new reply entry that closes the original
- Header shows "Conex la BTG-XXX" + "Inchide originala" badge when closing via conex
- After saving the new conex entry, parent is auto-closed with resolution "finalizat"
- onClose signature changed from (id: string) to (entry: RegistryEntry) across table + detail

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/modules/registratura/components/registry-entry-form.tsx

@@ -1311,28 +1311,38 @@ export function RegistryEntryForm({
               </Tooltip>
             </TooltipProvider>
           </Label>
-          {threadParent && (
+          {threadParentId && (
             <div className="mt-1.5 flex items-center gap-2 rounded border border-primary/30 bg-primary/5 px-2 py-1.5 text-sm">
-              <Badge
-                variant={
-                  threadParent.direction === "intrat" ? "default" : "secondary"
-                }
-                className="text-[10px]"
-              >
-                {threadParent.direction === "intrat" ? "↓" : "↑"}
-              </Badge>
-              <span className="font-mono text-xs">{threadParent.number}</span>
-              <span className="truncate text-muted-foreground text-xs">
-                {threadParent.subject}
-              </span>
+              {threadParent ? (
+                <>
+                  <Badge
+                    variant={
+                      threadParent.direction === "intrat" ? "default" : "secondary"
+                    }
+                    className="text-[10px]"
+                  >
+                    {threadParent.direction === "intrat" ? "\u2193" : "\u2191"}
+                  </Badge>
+                  <span className="font-mono text-xs">{threadParent.number}</span>
+                  <span className="truncate text-muted-foreground text-xs">
+                    {threadParent.subject}
+                  </span>
+                </>
+              ) : (
+                <span className="text-xs text-muted-foreground italic">
+                  Legat de o inregistrare (ID: {threadParentId.slice(0, 8)}...)
+                </span>
+              )}
               <Button
                 type="button"
                 variant="ghost"
                 size="sm"
-                className="ml-auto h-6 w-6 p-0"
+                className="ml-auto h-7 px-2 text-xs text-destructive hover:text-destructive"
                 onClick={() => setThreadParentId("")}
+                title="Sterge legatura"
               >
-                <X className="h-3.5 w-3.5" />
+                <X className="h-3.5 w-3.5 mr-0.5" />
+                Sterge
               </Button>
             </div>
           )}