PVC provisioning delays or failure due to "Not enough disk space"

**Note: This issue was generated with AI assistance (GitHub Copilot) based on automated log analysis and triage.**
Filed by @canonical/solutions-qa

## Problem Statement

Test executions for vault-k8s (and potentially other charms requiring persistent storage) are failing when the PersistentVolumeClaim (PVC) cannot be provisioned within the default 15-minute timeout window. The failure is triggered by a `JujuWaitTimeoutError`:

```
juju.backend.JujuWaitTimeoutError: Timed out while waiting for application to scale (applications: ['target'], units: ['target/0'])
```

Root cause analysis shows the PVC remains in `Pending` state due to storage resource exhaustion (e.g., not enough disk space). In some environments, the PVC may eventually be provisioned if resources are freed, but the test fails before this can occur due to timeout.

## Key Evidence

- Pod `target-0` stuck in Pending due to PVC provisioning delay.
- PVC event log: `ProvisioningFailed: Not enough disk space`
- Test Observer UI: [https://test-observer.canonical.com/#/charms/318313?testExecutionId=317949](https://test-observer.canonical.com/#/charms/318313?testExecutionId=317949)

No file or test is named. Start with the vault-k8s test execution and the 15-minute wait around JujuWaitTimeoutError, then determine whether the intended fix concerns timeout handling or storage-environment remediation. The issue does not specify completion criteria.

Written by the indexing model from the issue text.