feat: iam policy ressource add conditions and expire at

[pascalinthecloud]

Description

This PR introduces support for conditions in IAM policies. Conditions allow to restrict permissions based on resources, date or customer's information.

It also adds an expired_at attribute to policies.

The conditions attribute is implemented with a 3-level nested schema. This is a workaround for the fact that Terraform does not support recursive schema definitions. The depth of 3 levels was chosen as a reasonable default, but this can be adjusted in the future if needed.

This PR also includes two minor bug fixes:

• Fix a formatting issue in the ovh_cloud_project_network_private resource. This was a minor fix to remove an unnecessary fmt.Sprintf.
• Fix a formatting issue in the error handling of cloud project databases. This was a minor fix to add the correct format specifier to an fmt.Errorf call.

Type of change

• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

The new conditions and expired_at attributes have been tested with acceptance tests.

• Test A: make testacc TESTARGS="-run TestAccIamPolicy_conditions"
• Test B: make testacc TESTARGS="-run TestAccIamPolicy_withExpirationDate"
• Test C: make testacc TESTARGS="-run TestAccIamPolicy"

Test Configuration:

• Terraform version: terraform version: Terraform v1.11.3
• Existing HCL configuration you used:

resource "ovh_iam_policy" "workdays_and_ip_and_expiring" {
  name        = "workdays_and_ip_and_expiring"
  description = "Allow access only on workdays, expires end of 2026"
  identities  = ["urn:v1:eu:identity:user:my-user"]
  resources   = ["urn:v1:eu:resource:vps:*"]

  allow = [
    "vps:apiovh:*",
  ]

  conditions {
    operator = "AND"
    condition {
      operator = "MATCH"
      values = {
        "date(Europe/Paris).WeekDay.In" = "monday,tuesday,wednesday,thursday,friday"
      }
    }
    condition {
      operator = "MATCH"
      values = {
        "request.IP" = "192.72.0.1"
      }
    }
  }

  expired_at = "2026-12-31T23:59:59Z"
}

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my 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 or issues
• I have added acceptance tests that prove my fix is effective or that my feature works
• New and existing acceptance tests pass locally with my changes
• I ran successfully go mod vendor if I added or modify go.mod file