example(policies): add http-allowed-hostnames example

[migmartri]

Adds a policy example that calls the chainloop API remotely and compares the version. It's meant to showcase http-allowlist security capabilities of our policy engine.

note that an additional error state has been added to the testutils library so detect failed evaluations vs violations

./test.sh
Using Chainloop binary: chainloop

=== Policy Validation ===

Testing: Policy Lint Check
Command: chainloop policy develop lint --policy policy.yaml
✓ PASSED

Testing: No Allowed Hostnames - Should Fail the evaluation
Command: chainloop policy develop eval --policy policy.yaml --kind EVIDENCE  --material testdata/empty.json
✓ EVAL FAILED (as expected)

Testing: With Wrong Allowed Hostname - Should Fail
Command: chainloop policy develop eval --policy policy.yaml --kind EVIDENCE  --material testdata/empty.json --allowed-hostnames example.com
✓ EVAL FAILED (as expected)

Testing: With Correct Allowed Hostname  should run evaluation but fail because of version mismatch
Command: chainloop policy develop eval --policy policy.yaml --kind EVIDENCE  --material testdata/empty.json --allowed-hostnames app.chainloop.dev
✓ FAILED (as expected)

Fetching current platform version...
Current platform version: v0.256.0

Testing: Custom Expected Version (matching current platform)
Command: chainloop policy develop eval --policy policy.yaml --kind EVIDENCE  --material testdata/empty.json --allowed-hostnames app.chainloop.dev --input expected_version=v0.256.0
✓ PASSED

=== Test Results Summary ===

Total Tests: 5
Passed: 5
Failed: 0

🎉 All tests passed!

refs 2267