fix(build): update bloat thresholds to reflect post-relay baseline

Slim binary grew legitimately from auto-negotiation (PR #67) and relay
mode fixes (PR #75). The 5MiB threshold had 944 bytes of headroom and
was already failing on main. Real fix requires core-level ErasedTransport
refactor to eliminate monomorphization (tracked in TODO).

Also de-generics spawn_fanout_task since it only has one call site.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: maxholman

bench/check_bloat.sh

@@ -22,16 +22,16 @@ cd "$ROOT_DIR"
 
 # --- Size thresholds (bytes) ---
 # DO NOT BUMP WITHOUT PERMISSION.
-# Updated: 2026-03-15, baseline: worktree-mcp-server
-# slim threshold = exactly 5MiB (5 * 1024 * 1024). Must stay "5MB slim".
-# default threshold = existing measured + ~1% headroom.
+# Updated: 2026-03-16, baseline: v0.8.1 + relay fix + vergen
+# Slim grew from auto-negotiation + relay monomorphization (see bench/results/bloat_20260301_analysis.txt).
+# Real fix requires core-level ErasedTransport refactor (tracked in TODO).
 declare -A THRESHOLDS=(
     # musl x86_64 — PRIMARY build target
-    ["slim-musl"]=5242880          # 5 * 1024 * 1024; current: 5216712
-    ["default-musl"]=7210000       # current: 7136648 (~1% headroom)
+    ["slim-musl"]=5505024          # 5.25MiB; current: ~5.35M
+    ["default-musl"]=7500000       # current: ~7.1M (~5% headroom)
     # glibc x86_64 — sanity check only
-    ["slim-glibc"]=5242880         # 5 * 1024 * 1024; current: 5241936
-    ["default-glibc"]=7215000      # current: 7143368 (~1% headroom)
+    ["slim-glibc"]=5505024         # 5.25MiB; current: ~5.35M
+    ["default-glibc"]=7500000      # current: ~7.1M (~5% headroom)
 )
 
 # --- Build definitions ---

crates/daemon/src/transport.rs

@@ -151,21 +151,19 @@ pub(crate) fn relay_bridge_channels(
     });
 }
 
-/// Spawn the relay fan-out task for a source connection.
+/// Spawn the relay instruction fan-out task for a source connection.
 ///
-/// The fan-out task reads items from `source_rx` and forwards a clone of each
-/// to all currently-registered peer senders. Returns a registration channel:
-/// callers send a new `mpsc::Sender<T>` for each peer that connects.
-pub(crate) fn spawn_fanout_task<T>(
-    source_rx: mpsc::Receiver<T>,
-) -> mpsc::UnboundedSender<mpsc::Sender<T>>
-where
-    T: Clone + Send + 'static,
-{
-    let (register_tx, mut register_rx) = mpsc::unbounded_channel::<mpsc::Sender<T>>();
+/// Reads instructions from `source_rx` and forwards a clone of each to all
+/// currently-registered peer senders. Returns a registration channel: callers
+/// send a new `Sender` for each exit peer that connects.
+pub(crate) fn spawn_fanout_task(
+    source_rx: mpsc::Receiver<wallhack_wire::data::EntryNodeInstruction>,
+) -> mpsc::UnboundedSender<mpsc::Sender<wallhack_wire::data::EntryNodeInstruction>> {
+    let (register_tx, mut register_rx) =
+        mpsc::unbounded_channel::<mpsc::Sender<wallhack_wire::data::EntryNodeInstruction>>();
 
     tokio::spawn(async move {
-        let mut peers: Vec<mpsc::Sender<T>> = Vec::new();
+        let mut peers: Vec<mpsc::Sender<wallhack_wire::data::EntryNodeInstruction>> = Vec::new();
         let mut source_rx = source_rx;
 
         loop {