feat(persistence): add opt-in DocumentDB support

[sriaradhyula]

Description

Adds opt-in support for the MIT-licensed, PostgreSQL-backed DocumentDB project while keeping MongoDB as CAIPE's default persistence provider.

Design/default-provider discussion: #2419

• Adds caipe-documentdb profiles to the production and development Compose stacks.
• Adds --database=mongodb|documentdb and an interactive provider choice to setup-caipe.sh.
• Extends the caipe-ui-mongodb Helm subchart with provider: mongodb|documentdb and adds an umbrella-chart values example.
• Routes UI/BFF, Dynamic Agents, scheduler, autonomous agents, Slack, and Webex through the shared MONGODB_URI contract.
• Documents the provider choice, TLS expectations, and manual migration/rollback requirements.
• Pins DocumentDB Local to pg17-0.113.0; upstream 0.114.0 documents an active-connection regression.

MongoDB remains the default in .env.example, Compose profiles, setup-caipe, and Helm values. This PR does not migrate existing data or remove MongoDB support.

Related compatibility work: #886, #1321, #1924.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality not to work as expected)
• Documentation update

How Has This Been Tested?

• bash -n setup-caipe.sh
• bash tests/integration/test_setup_caipe_mongodb_password.sh (5 checks passed)
• uv run ruff check tests/test_documentdb_helm.py
• uv run pytest -q tests/test_documentdb_helm.py tests/test_mongodb_strict_passwords.py (18 passed)
• helm lint and helm template for both MongoDB and DocumentDB subchart paths
• Full umbrella-chart renders for both providers
• docker compose config --quiet for both providers in production and development Compose files
• Live DocumentDB Compose smoke test: PyMongo CRUD, compound unique index, aggregation, 17 MiB GridFS put/get/delete, and LangGraph MongoDBSaver persistence
• Validation-environment migration: 978 documents restored with exact collection counts and index comparisons; the source MongoDB was retained for rollback

The broader tests/test_helm_probes.py suite currently has unrelated baseline failures in standalone caipe-ui values and existing Dynamic Agents/ontology probe expectations (3 failures, 4 errors; 50 tests passed).

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[github-actions]

✅ No proprietary content detected. This PR is clear for review!

[caipe-ci-release]

Prebuild Artifacts for 0a7abd2

Branch: prebuild/feat/documentdb-support
Commit: 0a7abd2

Helm Charts

Chart	Registry	Version	Status	CI
ai-platform-engineering	ghcr.io/cnoe-io/prebuild-helm-charts	0.5.69-dev.4-feat-documentdb-support-1	Published	CI

Helm install commands

helm upgrade --install ai-platform oci://ghcr.io/cnoe-io/prebuild-helm-charts/ai-platform-engineering --version 0.5.69-dev.4-feat-documentdb-support-1

These prebuild artifacts will be automatically cleaned up when the PR is closed or merged.