### Does this PR have any customer impact?
Yes
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
Feature
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
Yes
### Are you introducing any new config? If yes, do you have tests with and without them being set?
No
### ChangeLog (Refer [Template](../oss/CHANGELOG.md))
### Description
Add support for hidden indexes with distributed tables.
- Add function that supports per node distribution with shards: Select all shards for the table and pick one shard per node.
- Add a planner worker function that executes on every shard
- On the shard skip execution if it's not the selected shard
- Run the local function on the worker function.
- Plumb in hooks to execute the index functions remotely.
----
#### AI description (iteration 1)
#### PR Classification
This pull request implements a new feature to support hidden indexes in a distributed environment.
#### PR Summary
The changes integrate hidden index support into distributed index update operations by introducing new per-node functions, updating API hooks, and modifying planner and UDF logic for proper shard routing and logging.
- **`node_distribution_operations.c`**: New file that adds functions (e.g., `UpdateDistributedPostgresIndex` and its worker) to execute index update commands per node in a distributed setting.
- **`diagnostic_commands_common.c`**: Introduces `command_node_worker` to ensure that update commands target the appropriate shard based on table identity.
- **`coll_mod.c` and `coll_mod.h`**: Updated to use `UpdatePostgresIndexWithOverride` and correctly incorporate hidden index modifications with distributed operations.
- **API hooks and metadata files** (e.g., `api_hooks.c`, `api_hooks_def.h`, `api_hooks.h`, and `metadata_cache.c`): Enhanced to support new function pointers and caching mechanisms for hidden index updates via the new command worker.
- **SQL UDF scripts**: New UDF definitions for `command_node_worker` and `update_postgres_index_worker` enable proper registration and execution of hidden index operations in the distributed framework.
<!-- GitOpsUserAgent=GitOps.Apps.Server.pullrequestcopilot -->
Signed-off-by: Shuai Tian <shuaitian@microsoft.com>
### Does this PR have any customer impact?
No
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
Refactoring
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
Yes
### Are you introducing any new config? If yes, do you have tests with and without them being set?
No
### Release Note (Refer [Template](../docs/release_notes/pgmongo_template.md))
### Description
Move type/operator/schema files from pg_helio_api -> pg_documentdb
Except udf files
----
#### AI description (iteration 1)
#### PR Classification
Code cleanup
#### PR Summary
This pull request moves type, operator, and schema files from the `pg_helio_api` directory to the `pg_documentdb` directory.
- Updated SQL include paths in multiple `pg_helio_api` SQL files to reference `pg_documentdb` directory.
- Modified `pgmongo` SQL files to include paths from `pg_documentdb` instead of `pg_helio_api`.
- Adjusted `validate_helio_extension_state.sh` script to account for new file paths.
- Updated `Makefile` in `pg_helio_api` to include the new directory structure.
- Changed include paths in `pg_documentdb_distributed` and `pg_helio_distributed` C source files to reflect the new directory structure.
### Does this PR have any customer impact?
No
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
Refactoring
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
No
### Are you introducing any new config? If yes, do you have tests with and without them being set?
No
### Release Note (Refer [Template](../docs/release_notes/pgmongo_template.md))
### Description
Remove helio references from documentdb
Remove helio references from documentdb_distributed
----
#### AI description (iteration 1)
#### PR Classification
Code cleanup
#### PR Summary
This pull request removes references to "helio" and replaces them with "documentdb" in the sources of `documentdb` and `documentdb_distributed`.
- `metadata_cache.h` and `metadata_cache.c`: Replaced "Helio" with "DocumentDB" in variable names and function names.
- `pgmongo.c`: Updated include statements and function calls to use "documentdb" instead of "helio".
- `planner.c`: Updated planner function and related calls to use "DocumentDBApiPlanner".
- Moved several header files from `helio_*` to `documentdb_*` naming convention without code changes.
- `commands_common.c` and `create_indexes.c`: Updated function calls and variable names to use "DocumentDB" instead of "Helio".
### Does this PR have any customer impact?
No
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
Refactor
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
No
### Are you introducing any new config? If yes, do you have tests with and without them being set?
### Release Note (Refer [Template](../docs/release_notes/pgmongo_template.md))
### Description
- Redo GUCs for helio -> documentdb preserving back-compat for the service.
- Move Docdb version to 1.24 -> 0.24
----
#### AI description (iteration 1)
#### PR Classification
API change
#### PR Summary
This pull request updates the prefix for all GUCs (Grand Unified Configuration) to a neutral prefix.
- `documentdb_init.c`: Changed GUCs from "helio_api" to a dynamic prefix using `psprintf`.
- `documentdb_distributed_init.c` and `documentdb_distributed.c`: Updated GUCs to use a dynamic prefix.
- `pg_documentdb.c`, `pg_helio_api.c`, and `pgmongo.c`: Modified initialization functions to pass the new GUC prefix.
- `helio_api_init.h` and `helio_distributed_init.h`: Updated function signatures to include the new GUC prefix parameter.
- Updated control files to reflect the new version `0.24-0`.
### Does this PR have any customer impact?
No
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
Refactor
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
No
### Are you introducing any new config? If yes, do you have tests with and without them being set?
No
### Release Note (Refer [Template](../docs/release_notes/pgmongo_template.md))
### Description
Move source files under new directory.
----
#### AI description (iteration 1)
#### PR Classification
Code reorganization
#### PR Summary
This pull request moves the `helio_api` and `helio_distributed` sources under the `documentdb` directory, updating references and initialization logic accordingly.
- Added `pg_documentdb.c` for initializing the `pg_documentdb` extension.
- Added `documentdb_distributed.c` for initializing the `pg_documentdb_distributed` extension.
- Updated `validate_helio_extension_state.sh` to include new checks for `documentdb`.
- Moved `helio_api_extension_version.c` to `documentdb_extension_version.c` without code changes.
- Updated various `Makefile` configurations to reflect the new directory structure and dependencies.
### Does this PR have any customer impact?
No
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
Refactor
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
Not yet
### Are you introducing any new config? If yes, do you have tests with and without them being set?
No
### Release Note (Refer [Template](../docs/release_notes/pgmongo_template.md))
### Description
Initial setup for documentdb extensions.
Create Makefiles and set up build scripts around documentdb.
This does not yet touch the actual code or make anything deployable.
----
#### AI description (iteration 1)
#### PR Classification
Initial setup for DocumentDB integration.
#### PR Summary
This pull request sets up the initial structure and configuration for DocumentDB integration.
- Added `documentdb_errors.h` for defining DocumentDB-specific error codes.
- Created `Makefile` for `pg_documentdb`, `pg_documentdb_core`, and `pg_documentdb_distributed` to handle build configurations.
- Updated `validate_helio_extension_state.sh` and `validate_headers.sh` scripts to include checks for DocumentDB.
- Modified `bson_aggregation_nested_pipeline.c`, `bson_aggregation_vector_search.c`, and other source files to replace references from Helio to DocumentDB.
- Added control files for `pg_documentdb`, `pg_documentdb_core`, and `pg_documentdb_distributed` extensions.
Vinod Sridharan
Zinan Ren