Remove policy scripts

Rhai made a decision about a route cost one to three microseconds,
some two hundred times what the same costs in Rust. That was bearable
where a function is asked once for an UPDATE, and is not where every
route is weighed against every peer, as it is when routes are passed
on. What is wanted of a policy (mark routes by where they came from,
mark what is announced, let communities say who is told what) needs no
language; it is to be configuration, done natively.

Kept from that work: route selection goes by a LOCAL_PREF that policy
set on a route from an external peer, and the lab's configuration can
be added to by a phase.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

crates/bench/Cargo.toml

@@ -18,7 +18,6 @@ stats_alloc = { version = "0.1.10", optional = true }
 
 [dev-dependencies]
 bgp-integration-tests.workspace = true
-bgp-policy.workspace = true
 bgp-rib.workspace = true
 bgp-server.workspace = true
 tokio.workspace = true
@@ -39,9 +38,5 @@ harness = false
 name = "real_table"
 harness = false
 
-[[bench]]
-name = "policy"
-harness = false
-
 [lints]
 workspace = true