proxy: Remove the endpoint filter cache (#12488)

## Problem

The endpoint filter cache is still unused because it's not yet reliable
enough to be used. It only consumes a lot of memory.

## Summary of changes

Remove the code. Needs a new design.

neondatabase/cloud#30634

proxy/src/rate_limiter/limiter.rs

@@ -16,44 +16,6 @@ use super::LeakyBucketConfig;
 use crate::ext::LockExt;
 use crate::intern::EndpointIdInt;
 
-pub struct GlobalRateLimiter {
-    data: Vec<RateBucket>,
-    info: Vec<RateBucketInfo>,
-}
-
-impl GlobalRateLimiter {
-    pub fn new(info: Vec<RateBucketInfo>) -> Self {
-        Self {
-            data: vec![
-                RateBucket {
-                    start: Instant::now(),
-                    count: 0,
-                };
-                info.len()
-            ],
-            info,
-        }
-    }
-
-    /// Check that number of connections is below `max_rps` rps.
-    pub fn check(&mut self) -> bool {
-        let now = Instant::now();
-
-        let should_allow_request = self
-            .data
-            .iter_mut()
-            .zip(&self.info)
-            .all(|(bucket, info)| bucket.should_allow_request(info, now, 1));
-
-        if should_allow_request {
-            // only increment the bucket counts if the request will actually be accepted
-            self.data.iter_mut().for_each(|b| b.inc(1));
-        }
-
-        should_allow_request
-    }
-}
-
 // Simple per-endpoint rate limiter.
 //
 // Check that number of connections to the endpoint is below `max_rps` rps.

proxy/src/rate_limiter/mod.rs

@@ -8,4 +8,4 @@ pub(crate) use limit_algorithm::aimd::Aimd;
 pub(crate) use limit_algorithm::{
     DynamicLimiter, Outcome, RateLimitAlgorithm, RateLimiterConfig, Token,
 };
-pub use limiter::{GlobalRateLimiter, RateBucketInfo, WakeComputeRateLimiter};
+pub use limiter::{RateBucketInfo, WakeComputeRateLimiter};