E2E: verify DP handles P0c kine fields (enforcement_mode, mandatory, direction) in real guardrail flow

Context

ai-gateway PR #411 adds enforcement_mode, mandatory, and direction to the outer aisix_core::Guardrail struct with #[serde(default)]. Unit tests (including p0c_fields_dont_trip_keyword_config_deny_unknown_fields) confirm the serde routing is correct.

However, there is no E2E test that boots a real DP, pushes a kine payload from AISIX-Cloud PR #516 that includes these three fields, and verifies the DP:

1. Parses the payload without error
2. Reads enforcement_mode=monitor correctly (i.e. does not block when it should only monitor)
3. Reads mandatory=true correctly
4. Reads direction=input correctly and applies it to hook filtering (when direction filtering is implemented)

What to add

Add an E2E test in the aisix-e2e compose suite under flows/ or live/ that:

• Creates a guardrail with enforcement_mode=monitor, mandatory=false, direction=both via the CP API
• Attaches it to an env-scope
• Sends a chat request that would trigger the guardrail keyword match
• Asserts the request is allowed through (monitor mode, not block)
• Asserts the usage event records the guardrail match with enforcement_mode=monitor

Priority

LOW — the DP unit tests pin the serde contract; this E2E test verifies the full CP→kine→DP pipeline. Should be added before the enforcement_mode field is used in product UI (i.e. before the dashboard exposes it as a real control).

Related

• ai-gateway PR #411
• AISIX-Cloud PR #516
• #379 P0c checklist

Start with the aisix-e2e compose suite under flows/ or live/ and its existing CP API flows, then trace the real CP→kine→DP path. Create the specified guardrail and env-scope, send a keyword-triggering chat request, and verify it is allowed while the usage event records the match and enforcement_mode=monitor.