test(contrib/drivers/pgsql): add SoftTime, With, ScanList test coverage (#4676)

## Summary
- Add 3 new test files for pgsql driver (39 test functions, ~3800 lines)
- `pgsql_z_unit_feature_soft_time_test.go`: 15 tests — soft delete
(SoftDeleted/Unscoped), auto time fields
(CreatedAt/UpdatedAt/DeletedAt), time format options
- `pgsql_z_unit_feature_with_test.go`: 17 tests — With relation queries
(one-to-one, one-to-many, many-to-many), nested With, WithAll,
conditional With
- `pgsql_z_unit_feature_scanlist_test.go`: 7 tests — ScanList relation
mapping for struct slices
- Add testdata SQL templates for With tests

**PostgreSQL adaptations from MySQL:**
- `AUTO_INCREMENT` → `SERIAL/BIGSERIAL`
- `datetime` → `timestamp`
- MySQL backticks → PostgreSQL double quotes for identifiers
- Timestamp format handling for soft time fields

## Test plan
- [x] Run `go test -v -run "Test_Model_Soft" -count=1` in
`contrib/drivers/pgsql`
- [x] Run `go test -v -run "Test_Model_With" -count=1` in
`contrib/drivers/pgsql`
- [x] Run `go test -v -run "Test_Model_ScanList" -count=1` in
`contrib/drivers/pgsql`

ref #4689

contrib/drivers/pgsql/testdata/with_multiple_depends.sql

@@ -0,0 +1,30 @@
+
+CREATE TABLE table_a (
+    id SERIAL PRIMARY KEY,
+    alias varchar(255) DEFAULT ''
+);
+
+INSERT INTO table_a VALUES (1, 'table_a_test1');
+INSERT INTO table_a VALUES (2, 'table_a_test2');
+
+CREATE TABLE table_b (
+    id SERIAL PRIMARY KEY,
+    table_a_id integer NOT NULL,
+    alias varchar(255) DEFAULT ''
+);
+
+INSERT INTO table_b VALUES (10, 1, 'table_b_test1');
+INSERT INTO table_b VALUES (20, 2, 'table_b_test2');
+INSERT INTO table_b VALUES (30, 1, 'table_b_test3');
+INSERT INTO table_b VALUES (40, 2, 'table_b_test4');
+
+CREATE TABLE table_c (
+    id SERIAL PRIMARY KEY,
+    table_b_id integer NOT NULL,
+    alias varchar(255) DEFAULT ''
+);
+
+INSERT INTO table_c VALUES (100, 10, 'table_c_test1');
+INSERT INTO table_c VALUES (200, 10, 'table_c_test2');
+INSERT INTO table_c VALUES (300, 20, 'table_c_test3');
+INSERT INTO table_c VALUES (400, 30, 'table_c_test4');

contrib/drivers/pgsql/testdata/with_tpl_user.sql

@@ -0,0 +1,4 @@
+CREATE TABLE IF NOT EXISTS %s (
+    id SERIAL PRIMARY KEY,
+    name varchar(45) NOT NULL
+);

contrib/drivers/pgsql/testdata/with_tpl_user_detail.sql

@@ -0,0 +1,4 @@
+CREATE TABLE IF NOT EXISTS %s (
+    uid SERIAL PRIMARY KEY,
+    address varchar(45) NOT NULL
+);

contrib/drivers/pgsql/testdata/with_tpl_user_scores.sql

@@ -0,0 +1,5 @@
+CREATE TABLE IF NOT EXISTS %s (
+    id SERIAL PRIMARY KEY,
+    uid integer NOT NULL,
+    score integer NOT NULL
+);