### Does this PR have any customer impact?
Yes
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
Perf
### 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?
### ChangeLog (Refer [Template](../oss/CHANGELOG.md))
### Description
Currently for Update/Delete, we currently parse the update spec, query spec, etc into pgbsons on startup. Then reuse it per commands.
This has a few issues - for large document requests, this causes us to duplicate memory and persist it for the duration of the update and also transcode all up front - this is worse for multi-node when all we need to do is build yet another update spec and push it to the worker.
Instead, we now only cache pointers to the spec document; then when we need it we convert to pgbson only if necessary.
A consequence of this is that on a single node update, if we're doing a simple updateOne on _id then we would never serialize the updateSpec at all (for instance).
We also more eagerly free memory on the intermediate update specs.
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#### AI description (iteration 1)
#### PR Classification
Performance optimization for update parsing by refactoring BSON value handling.
#### PR Summary
This PR streamlines update parsing by replacing heavy BSON initialization routines with lightweight wrappers and converting update-related types from `pgbson*` to `bson_value_t*`, which reduces overhead and improves coordinator/worker compatibility.
- `src/commands/update.c`: Replaced multiple `PgbsonInitFromDocumentBsonValue` and similar calls with efficient wrappers like `CreateBsonValueFrom` and updated serialization (including back-compatible array filter and update document formats).
- `include/commands/update.h`: Updated update structure fields to use `bson_value_t*` instead of `pgbson*`, aligning interfaces with the new parsing approach.
- `src/update/bson_update.c` and `bson_update_operators_workflow.c`: Refactored update type determination and replace document logic to use new BSON value iterators and helper functions.
- Other modules (e.g. `commands/find_and_modify.c`, `commands/delete.c`, query operators, sharding) were updated to leverage the lighter-weight BSON representation and its associated helper routines.
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### Does this PR have any customer impact? No
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc) Feature
### 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
### ChangeLog (Refer [Template](../oss/CHANGELOG.md))
### Description
Support collation for aggregation and query match queries on sharded collections.
If the `shard key filter` is collation-aware, we make the query distributed and push it to all shards.
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#### AI description (iteration 1)
#### PR Classification
New feature: Collation support for aggregation and query match on sharded collections.
#### PR Summary
This pull request adds collation support for aggregation and query match operations on sharded collections.
- `bson_dollar_ops_collation_tests_runtime.sql`: Added tests for collation-aware shard key queries.
- `sharding.c`: Introduced logic to track collation-aware shard key fields and updated related functions.
- `query_operator.c`: Modified to include shard key filters only if they are not collation-sensitive.
- `bson_aggregation_pipeline.c`: Added collation-aware checks for shard key filters in aggregation pipelines.
- `bson_query.h`: Added utility function `IsBsonTypeCollationAware` to check if BSON types are collation-aware.
<!-- GitOpsUserAgent=GitOps.Apps.Server.pullrequestcopilot -->
Related work items: #3915171, #3922023
### 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.
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#### 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.
Vinod Sridharan
Cornelius Boateng