Add MifosX smoke tests to improve deployment verification

[iamshashankyadav]

Description

This PR adds a lightweight smoke-test layer for MifosX deployments in Mifos Gazelle.

The new checks validate:

• MifosX namespace readiness
• MifosX web app reachability
• tenant-aware Fineract API availability

The smoke tests are designed to be fault-tolerant:

• they are isolated from the main deployment flow
• they can run in non-strict mode without affecting normal Gazelle deployments
• they can run in strict mode in CI to catch regressions early

Why this change

The DMP scope is focused on shipping the latest version of Mifos X in Gazelle.
Before upgrading MifosX safely, Gazelle needs a reliable way to confirm that a deployed version is actually healthy.

This PR helps build that safety net by introducing basic post-deployment verification for MifosX. That makes it easier to:

• detect regressions during future MifosX upgrades
• improve confidence when changing MifosX version pins or manifests
• support shipping the latest version of Mifos X with lower deployment risk

Changes made

• implemented test_mifosx() in src/deployer/deployer.sh
• added reusable smoke-test helpers for HTTP/status validation
• added src/utils/smoke-tests.sh as a standalone smoke-test runner
• updated CircleCI to run MifosX smoke tests in strict mode

Testing

Tested by:

• verifying the smoke-test flow and script wiring in the repo
• ensuring the smoke-test path is separated from the main deployment path
• confirming CI now targets MifosX smoke verification only

Notes

This PR intentionally focuses only on MifosX because that is the current upgrade target under DMP/C4GT scope.