SV1_SCAN_BIGQUERY deployment var; allow BQ-only cleanup

[stephencompall-DA]

Fixes #1060. Tested by deploying scratchb with the new SV1_SCAN_BIGQUERY variable, manually removing the replication slot and publication from the CloudSQL instance (and disabling the variable), and reapplying.

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[Copilot]

Pull Request Overview

This PR prepares for conditional activation (and later deactivation) of BigQuery scanning for the SV1 service by adding an environment flag and refactoring SQL import commands.

• Introduce SV1_SCAN_BIGQUERY env flag to toggle scanBigQuery config in svConfigs.ts
• Add retainOnDelete to the Postgres replicator user and extract common shell command chunks into databaseCommandBracket in bigQuery.ts
• Refactor createPublicationAndReplicationSlots to use the new header/footer helper

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
cluster/pulumi/common-sv/src/svConfigs.ts	Add SV1_SCAN_BIGQUERY flag and conditional scanBigQuery
cluster/pulumi/canton-network/src/bigQuery.ts	Refactor SQL import commands into databaseCommandBracket, update replicator user creation

Comments suppressed due to low confidence (2)

cluster/pulumi/common-sv/src/svConfigs.ts:63

• Consider adding unit or integration tests to verify that enabling or disabling SV1_SCAN_BIGQUERY correctly includes or omits the scanBigQuery configuration.

...(sv1ScanBigQuery
          ? { scanBigQuery: { dataset: 'mainnet_da2_scan', prefix: 'da2' } }

cluster/pulumi/canton-network/src/bigQuery.ts:314

• [nitpick] The constant name is very generic. Rename it to something like resourceName or userResourceName for clearer intent.

const name = `${postgres.namespace.logicalName}-user-${replicatorUserName}`;

[Copilot]

[nitpick] Add a doc comment above databaseCommandBracket explaining its purpose and the structure of the header/footer shapes to improve readability and maintainability.

Suggested change

	/**
	* Generates a set of shell commands for managing temporary SQL files and importing them into a Cloud SQL database.
	*
	* @param postgres - The CloudPostgres instance containing database and service account details.
	* @returns An object with `header` and `footer` properties:
	* - `header`: A shell script segment that sets up a temporary GCS bucket, grants access, and prepares a SQL file.
	* - `footer`: A shell script segment that uploads the SQL file to GCS, imports it into the database, and cleans up resources.
	*/

[ray-roestenburg-da]

Thanks!