Revert "Delete vendor/ and the route proxy's: the build module fetches the modules, the root image builds with -mod=mod (issue 1305, C6)"

This reverts commit 9c4bf1f08b.

vendor/github.com/antithesishq/antithesis-sdk-go/assert/assert_noop.go

@@ -0,0 +1,16 @@
+//go:build !enable_antithesis_sdk
+
+package assert
+
+func Always(condition bool, message string, details map[string]any)              {}
+func AlwaysOrUnreachable(condition bool, message string, details map[string]any) {}
+func Sometimes(condition bool, message string, details map[string]any)           {}
+func Unreachable(message string, details map[string]any)                         {}
+func Reachable(message string, details map[string]any)                           {}
+func AssertRaw(cond bool, message string, details map[string]any,
+	classname, funcname, filename string, line int,
+	hit bool, mustHit bool,
+	assertType string, displayType string,
+	id string,
+) {
+}