Foro: paginación en la búsqueda y contador de visitas por tema

- búsqueda paginada (count_search_topics + offset/limit) con controles en la plantilla
- contador de visitas: columna opcional forum_topics.views con detección automática
  (has_views_column), increment_views al ver el tema, mostrado en lista y cabecera
- sql/forum_views.sql (ALTER opcional) + docs

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

forum/db.py

@@ -25,6 +25,35 @@ def _conn():
     return connections['acore_web']
 
 
+# Detección perezosa de la columna opcional forum_topics.views (contador de visitas)
+_views_supported = None
+
+
+def has_views_column():
+    global _views_supported
+    if _views_supported is None:
+        try:
+            with _conn().cursor() as cursor:
+                cursor.execute("SELECT views FROM forum_topics LIMIT 1")
+            _views_supported = True
+        except Exception:
+            _views_supported = False
+    return _views_supported
+
+
+def increment_views(topic_id):
+    """Suma 1 a las visitas del tema (si existe la columna)."""
+    if not has_views_column():
+        return
+    try:
+        with _conn().cursor() as cursor:
+            cursor.execute(
+                "UPDATE forum_topics SET views = views + 1 WHERE id = %s", [topic_id]
+            )
+    except Exception:
+        pass
+
+
 # --------------------------------------------------------------------------
 # Portada: categorías + foros (con estadísticas)
 # --------------------------------------------------------------------------
@@ -110,11 +139,12 @@ def count_topics(forum_id):
 
 
 def get_topics(forum_id, offset, limit):
+    views_sel = "t.views," if has_views_column() else "0 AS views,"
     with _conn().cursor() as cursor:
         cursor.execute(
-            """
+            f"""
             SELECT t.id, t.name, t.poster, t.poster_id, t.created, t.sticky,
-                   t.locked, t.moved, t.updated_at,
+                   t.locked, t.moved, t.updated_at, {views_sel}
                    (SELECT COUNT(*) FROM forum_posts p
                       WHERE p.topic_id = t.id AND p.deleted = 0) AS post_count,
                    (SELECT p2.poster FROM forum_posts p2
@@ -138,10 +168,11 @@ def get_topics(forum_id, offset, limit):
 # --------------------------------------------------------------------------
 
 def get_topic(topic_id, include_hidden=False):
+    views_sel = ", views" if has_views_column() else ", 0 AS views"
     with _conn().cursor() as cursor:
         cursor.execute(
             "SELECT id, forum_id, name, poster, poster_id, created, sticky, "
-            "locked, deleted, moved, updated_at FROM forum_topics WHERE id = %s",
+            f"locked, deleted, moved, updated_at{views_sel} FROM forum_topics WHERE id = %s",
             [topic_id],
         )
         topic = _dictfetchone(cursor)
@@ -333,22 +364,38 @@ def get_display_name(poster_id):
     return None
 
 
-def search_topics(query, limit=50):
+def count_search_topics(query):
+    like = f"%{query}%"
+    with _conn().cursor() as cursor:
+        cursor.execute(
+            """
+            SELECT COUNT(DISTINCT t.id)
+            FROM forum_topics t
+            JOIN forums f ON f.id = t.forum_id AND f.visibility = 1 AND f.deleted = 0
+            LEFT JOIN forum_posts p ON p.topic_id = t.id AND p.deleted = 0
+            WHERE t.deleted = 0 AND (t.name LIKE %s OR p.text LIKE %s)
+            """,
+            [like, like],
+        )
+        return cursor.fetchone()[0]
+
+
+def search_topics(query, offset=0, limit=20):
     """Busca temas por título o por contenido de sus posts (foros visibles)."""
     like = f"%{query}%"
     with _conn().cursor() as cursor:
         cursor.execute(
             """
             SELECT DISTINCT t.id, t.name, t.poster, t.poster_id, t.forum_id,
-                   t.created, f.name AS forum_name
+                   t.created, t.updated_at, f.name AS forum_name
             FROM forum_topics t
             JOIN forums f ON f.id = t.forum_id AND f.visibility = 1 AND f.deleted = 0
             LEFT JOIN forum_posts p ON p.topic_id = t.id AND p.deleted = 0
             WHERE t.deleted = 0 AND (t.name LIKE %s OR p.text LIKE %s)
             ORDER BY t.updated_at DESC
-            LIMIT %s
+            LIMIT %s OFFSET %s
             """,
-            [like, like, limit],
+            [like, like, limit, offset],
         )
         return _dictfetchall(cursor)