feat(query): AST de filtre + compilateur ast_to_sql (#41)

Ajoute une représentation canonique du filtre sous forme d'AST booléen
(Condition/And/Or/Not) et son compilateur vers SQL DuckDB paramétré
(ast_to_sql). Réutilise tokenize_text_filter pour les feuilles texte.

Fondation pour la migration /tableau vers dash-ag-grid : cet AST sera
alimenté par le filterModel d'AG Grid (tâche suivante) et, plus tard,
par un champ de requête booléenne libre (#97).

tests/test_query_ast.py

@@ -0,0 +1,106 @@
+import polars as pl
+
+from src.utils.query_ast import And, Condition, Not, Or, ast_to_sql
+
+SCHEMA = pl.Schema(
+    {
+        "acheteur_nom": pl.String,
+        "objet": pl.String,
+        "montant": pl.Float64,
+        "dureeMois": pl.Int64,
+        "dateNotification": pl.Date,
+    }
+)
+
+
+def _run(node):
+    """Compile et retourne (sql, params)."""
+    return ast_to_sql(node, SCHEMA)
+
+
+def test_none_is_true():
+    assert _run(None) == ("TRUE", [])
+
+
+def test_empty_and_is_true():
+    assert _run(And([])) == ("TRUE", [])
+
+
+def test_text_contains_uses_ilike_and_params():
+    sql, params = _run(Condition("objet", "contains", "voirie"))
+    assert "ILIKE ?" in sql
+    assert params == ["%voirie%"]
+
+
+def test_text_contains_multiword_is_and():
+    sql, params = _run(Condition("objet", "contains", "metropole rennes"))
+    assert sql.count("ILIKE ?") == 2
+    assert params == ["%metropole%", "%rennes%"]
+
+
+def test_text_contains_wildcard_and_phrase():
+    _, params = _run(Condition("objet", "contains", "distri* metropole+rennes"))
+    assert params == ["distri%", "%metropole rennes%"]
+
+
+def test_text_notcontains_negates():
+    sql, params = _run(Condition("objet", "notContains", "construction"))
+    assert "NOT (" in sql
+    assert params == ["%construction%"]
+
+
+def test_numeric_gt():
+    sql, params = _run(Condition("montant", "gt", 40000))
+    assert '"montant" > ?' in sql
+    assert params == [40000.0]
+
+
+def test_numeric_eq_int_column():
+    sql, params = _run(Condition("dureeMois", "eq", "12"))
+    assert '"dureeMois" = ?' in sql
+    assert params == [12]
+
+
+def test_numeric_range():
+    sql, params = _run(Condition("montant", "range", 100, 200))
+    assert params == [100.0, 200.0]
+    assert "BETWEEN" in sql or ("> ?" in sql and "< ?" in sql)
+
+
+def test_numeric_invalid_value_is_true():
+    # valeur non numérique -> condition neutralisée (TRUE), pas d'exception
+    assert _run(Condition("montant", "gt", "abc")) == ("TRUE", [])
+
+
+def test_date_gt_casts_varchar():
+    sql, params = _run(Condition("dateNotification", "gt", "2022"))
+    assert "VARCHAR" in sql
+    assert params == ["2022"]
+
+
+def test_blank_and_notblank():
+    sql_b, _ = _run(Condition("objet", "blank"))
+    assert "IS NULL" in sql_b
+    sql_nb, _ = _run(Condition("objet", "notBlank"))
+    assert "IS NOT NULL" in sql_nb
+
+
+def test_unknown_column_is_true():
+    assert _run(Condition("colonne_inexistante", "contains", "x")) == ("TRUE", [])
+
+
+def test_and_or_not_grouping():
+    node = And(
+        [
+            Or(
+                [
+                    Condition("objet", "contains", "beton"),
+                    Condition("objet", "contains", "ciment"),
+                ]
+            ),
+            Not(Condition("objet", "contains", "demolition")),
+        ]
+    )
+    sql, params = _run(node)
+    assert " OR " in sql and " AND " in sql and "NOT (" in sql
+    assert params == ["%beton%", "%ciment%", "%demolition%"]