This PR is the follow-up of #7556.

Currently, the Gateway API translator sets HTTPRoute Accepted condition as false when any of the its rules is invalid. This PR changes the behavior to set Accepted as false only if all rules are invalid, if both valid and invalid rules exist, the Accepted is set to true, and a PartiallyInvalid condition is added to the status.

The updated behavior aligns with the Gateway API spec.

https://gateway-api.sigs.k8s.io/geps/gep-1364/

A HTTPRoute with two rules, one valid and one which specifies a HTTPRequestRedirect filter _and a HTTPURLRewrite filter. Accepted is true, because the valid rule can produce some config in the data plane. We'll need to raise the more specific error condition for an incompatible filter combination as well to make the partial validity clear.

RouteConditionPartiallyInvalid:

// This condition indicates that the Route contains a combination of both
// valid and invalid rules.
//
// When this happens, implementations MUST take one of the following
// approaches:
//
// 1) Drop Rule(s): With this approach, implementations will drop the
// invalid Route Rule(s) until they are fully valid again. The message
// for this condition MUST start with the prefix "Dropped Rule" and
// include information about which Rules have been dropped. In this
// state, the "Accepted" condition MUST be set to "True" with the latest
// generation of the resource.
// 2) Fall Back: With this approach, implementations will fall back to the
// last known good state of the entire Route. The message for this
// condition MUST start with the prefix "Fall Back" and include
// information about why the current Rule(s) are invalid. To represent
// this, the "Accepted" condition MUST be set to "True" with the
// generation of the last known good state of the resource.

Fix: #7545