feat(contrib/drivers/gaussdb): add gaussdb driver support (#4563)

This pull request introduces a new database driver for openGauss
(GaussDB), integrating it into the GoFrame framework. The implementation
includes connection handling, SQL execution, type conversion, and other
driver-specific logic. Additionally, the CI workflow is updated to
include an openGauss server for testing. The main themes are: new driver
implementation, SQL and type handling, and CI integration.

**GaussDB Driver Implementation:**

* Added a new driver in `contrib/drivers/gaussdb` to support
openGauss/GaussDB databases, including initialization, connection
handling, and registration with GoFrame's database abstraction.
(`gaussdb.go`, `gaussdb_open.go`)
[[1]](diffhunk://#diff-4f0d2a9160a039ccdf1dc98205ed7cd9f3bb8d606fed57c5a4813937eecca81fL11-R49)
[[2]](diffhunk://#diff-a0534a00c87159a3a3d2ea20a9779ead115cc7e38ab274484cfd4b2aa86b6055R1-R69)
* Implemented custom SQL execution and result handling to support
GaussDB's PostgreSQL-based features, including primary key handling on
insert and custom result types. (`gaussdb_do_exec.go`,
`gaussdb_result.go`)
[[1]](diffhunk://#diff-528b2ec06651f4af022e0550526794a606bf257d59bc18b6bce58373c784a2f2R1-R110)
[[2]](diffhunk://#diff-ad33dffe3bbccae20b113e3865aa491ef3b54c68ef586a89cf09a581a1c2abedR1-R24)

**SQL and Type Handling:**

* Added SQL filtering and placeholder conversion to support
PostgreSQL-style parameterization and GaussDB-specific SQL quirks, such
as handling `INSERT IGNORE` and JSONB syntax. (`gaussdb_do_filter.go`)
* Implemented comprehensive type conversion logic for mapping
PostgreSQL/GaussDB types to Go types, including arrays, UUIDs, and
custom handling for JSON and numeric types. (`gaussdb_convert.go`)
* Provided a function for random ordering (`ORDER BY RANDOM()`) and
explicitly disabled upsert/ON CONFLICT support, as GaussDB does not
support this feature. (`gaussdb_order.go`, `gaussdb_format_upsert.go`)
[[1]](diffhunk://#diff-510fc9393899057fddacc7dd6d14f0ca2fff145b52341dd3cfa5db48c960e5c1R1-R12)
[[2]](diffhunk://#diff-c89496520a15032be867e26861b248f11557cc45d683b5216ca1756949a7b9adR1-R94)

**CI Integration:**

* Updated the CI workflow to start an openGauss server in Docker,
enabling automated tests against the new driver.
(`.github/workflows/ci-main.yml`)

---------

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

.github/workflows/ci-main.yml

@@ -198,6 +198,17 @@ jobs:
         ports:
           - 5236:5236
 
+      # openGauss server
+      # docker run --privileged=true -e GS_PASSWORD=UTpass@1234 -p 9950:5432 opengauss/opengauss:7.0.0-RC1.B023
+      gaussdb:
+        image: opengauss/opengauss:7.0.0-RC1.B023
+        env:
+          GS_PASSWORD: UTpass@1234
+          TZ: Asia/Shanghai
+        ports:
+          - 9950:5432
+
+
       zookeeper:
         image: zookeeper:3.8
         ports: