Azure.Sdk.Tools.TestProxy_1.0.0-dev.20250915.5

Support `standard` proxy mode in test-proxy (#11958)

* adding new `--http-proxy` mode to the test-proxy. This enables the proxy to act as a real HTTP_PROXY configured proxy.
* Add tests for this new "standard proxy mode" + some adjustments to recorded test to ensure tests aren't broken
* updating `1es-redirect` permissiveness setting to `Permissive` for everyone using `1es-redirect.yml`