Move route-proxy out of the controller's repository, which is archived with the controller

route-proxy provides `route` to five modules and lived in novox/mesh-controller, archived once the controller is
removed (issue 1126). Its history comes along (git filter-repo of modules/route-proxy and its earlier home
examples/route-proxy). Its contract's Go module path names this repository, and route-proxy builds the contract from
its own tree through a replace, so no tag is needed before the first build. The two manifest tests that held its
public ACME account and mounted program lived in the controller's internal/ownmanifest; they move beside the module.

Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL

modules/route-proxy/go.sum

@@ -1,5 +1,3 @@
-git.novox.be/novox/mesh-controller/modules/route-proxy/contract v0.1.0 h1:89jE1oBK+l7gFJjz6wx8mUD3KxrqSDa7pUTlQkzC1do=
-git.novox.be/novox/mesh-controller/modules/route-proxy/contract v0.1.0/go.mod h1:Yr+Xp89kpMiKH6kA06EU+d9I2CyzrK9yMX7J3pSv0hE=
 git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261101022206-8af6e7266915 h1:x8k7IeMirMTxUo8BH+xUO+MDnHYgU+636jl1NIw1wvs=
 git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261101022206-8af6e7266915/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
 github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op h1:Z/MZK75wC/NSrkgqeNIa7jexam9uWzhLmFTSCPI/kn0=