fix: add multigres into acceptance matrix

[ferhatelmas]

What kind of change does this PR introduce?

Bug fix

What is the current behavior?

Multigres doesn't have acceptance matrix, only integration.

What is the new behavior?

Multigres is a matrix entry for acceptance tests.

Additional context

Switching multigres image to latest (unlogged table support is reverted and pgvector is already included)
Gateway doesn't support provisioning multiple databases, so single tenant vector tests live in a different schema but not in a different database unlike pg/oriole and it's configured via env defaults to pg/orioledb to create a new database.
Extract multigres pull into a composite action for reuse.
Update instance type since matrix has 12 combinations now.

[Copilot]

Pull request overview

This PR expands CI/acceptance coverage by adding Multigres to the local acceptance matrix and adjusting pgvector single-tenant behavior so vector-store migrations/runtime can run without CREATE DATABASE (needed for gateways like Multigres).

Changes:

• Add VECTOR_DATABASE_CREATE config flag to disable CREATE DATABASE storage_vectors and instead run vector migrations/runtime directly against VECTOR_DATABASE_URL.
• Extend the acceptance workflow matrix to include multigres and wire the appropriate infra restart + env defaults.
• Factor Multigres image pulling into a reusable composite GitHub Action and switch Multigres infra to use the latest image tag.

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/internal/database/migrations/vector-store-migrations.test.ts	Adds coverage for single-tenant vector migrations when DB creation is disabled.
src/internal/database/migrations/migrate.ts	Threads vectorDatabaseCreate into the vector migration runner in single-tenant mode.
src/http/plugins/vector.ts	Aligns runtime pgvector connection target with VECTOR_DATABASE_CREATE.
src/config.ts	Introduces vectorDatabaseCreate config parsing from VECTOR_DATABASE_CREATE.
package.json	Adds a Multigres+pgvector test script with VECTOR_DATABASE_CREATE=false.
acceptance/scripts/run-managed-local.ts	Allows infra:restart:ci:multigres for managed-local acceptance runs.
acceptance/README.md	Documents Multigres vector acceptance behavior and the new flag.
.github/workflows/ci.yml	Replaces inline Multigres pull logic with the new composite action.
.github/workflows/acceptance.yml	Adds Multigres to the acceptance matrix and configures env/restart logic.
.github/actions/pull-multigres-cluster/action.yml	New composite action to pull the Multigres image with retries.
.docker/docker-compose-infra-multigres-override.yml	Switches Multigres image reference to ghcr.io/multigres/multigres-cluster:latest.

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[coveralls]

Coverage Report for CI Build 27017816367

Coverage increased (+0.07%) to 76.416%

Details

• Coverage increased (+0.07%) from the base build.
• Patch coverage: 1 uncovered change across 1 file (0 of 1 lines covered, 0.0%).
• 1 coverage regression across 1 file.

Uncovered Changes

File	Changed	Covered	%
src/http/plugins/vector.ts	1	0	0.0%

Coverage Regressions

1 previously-covered line in 1 file lost coverage.

File	Lines Losing Coverage	Coverage
src/http/plugins/vector.ts	1	56.92%

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Coverage Stats

Relevant Lines:	11022
Covered Lines:	8853
Line Coverage:	80.32%
Relevant Branches:	6460
Covered Branches:	4506
Branch Coverage:	69.75%
Branches in Coverage %:	Yes
Coverage Strength:	368.96 hits per line

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💛 - Coveralls