refactor(serverless): remove dead code introduced on branch

- Delete orphaned HarnessRelay::connect() wrapper (callers use
  connect_with_mode); fold its doc into connect_with_mode.
- Gate BgState::new() behind #[cfg(test)] (test-only now that the
  runtime path uses with_serverless) instead of #[allow(dead_code)].
- Move KIND_GIFT_WRAP into the encrypted test module (test-only).

No #[allow(dead_code)] / cfg_attr dead-code suppressions remain on
branch-new code. Verified with RUSTFLAGS='-D dead_code -D unused'.

crates/sprout-acp/src/relay.rs

@@ -656,24 +656,12 @@ impl RelayEventPublisher {
 impl HarnessRelay {
     // ── Public API ────────────────────────────────────────────────────────────
 
-    /// Connect to relay and authenticate via NIP-42.
+    /// Connect to the relay, optionally in serverless mode (generic relay, AUTH
+    /// optional, plain-WS reads/writes). In server mode (`serverless = false`)
+    /// the NIP-42 AUTH handshake is performed; in serverless mode it is skipped.
     ///
     /// `auth_tag` is an optional NIP-OA owner attestation included in the AUTH
     /// event for relay membership delegation.
-    /// Server-mode convenience wrapper around [`HarnessRelay::connect_with_mode`].
-    /// Kept as part of the public API; the binary uses `connect_with_mode`.
-    #[allow(dead_code)]
-    pub async fn connect(
-        relay_url: &str,
-        keys: &Keys,
-        agent_pubkey_hex: &str,
-        auth_tag: Option<nostr::Tag>,
-    ) -> Result<Self, RelayError> {
-        Self::connect_with_mode(relay_url, keys, agent_pubkey_hex, auth_tag, false).await
-    }
-
-    /// Connect, optionally in serverless mode (generic relay, AUTH optional,
-    /// plain-WS reads/writes). See [`HarnessRelay::connect`].
     pub async fn connect_with_mode(
         relay_url: &str,
         keys: &Keys,
@@ -1133,9 +1121,9 @@ struct BgState {
 }
 
 impl BgState {
-    /// Server-mode constructor. Used by unit tests; the runtime path uses
+    /// Server-mode constructor. Test-only; the runtime path uses
     /// [`BgState::with_serverless`].
-    #[allow(dead_code)]
+    #[cfg(test)]
     fn new() -> Self {
         Self::with_serverless(false)
     }

desktop/src-tauri/src/encrypted.rs

@@ -26,10 +26,6 @@
 use nostr::nips::nip59::UnwrappedGift;
 use nostr::{Event, EventBuilder, Keys, PublicKey, UnsignedEvent};
 
-/// Kind 1059 — NIP-59 gift wrap.
-#[cfg_attr(not(test), allow(dead_code))]
-pub const KIND_GIFT_WRAP: u16 = 1059;
-
 /// Build the gift-wrapped events for `rumor`, one per recipient pubkey.
 ///
 /// `rumor` is the unsigned inner event (a normal kind-9 message with the `h`
@@ -99,6 +95,9 @@ impl UnwrappedRumor {
 #[cfg(test)]
 mod tests {
     use super::*;
+
+    /// Kind 1059 — NIP-59 gift wrap (test-only constant).
+    const KIND_GIFT_WRAP: u16 = 1059;
     use nostr::Kind;
 
     fn rumor(sender: &Keys, channel_id: &str, content: &str) -> UnsignedEvent {