feat(sidecar): protocol 14 — POST /kits/uses (PLAN_REDESIGNS §2.6)

Opens protocol 14 (D332) for the step editor: one thin forward, POST /kits/uses
-> kits.uses ({kit, steamIds} in, counts out), for the kit weekend's warning.
perm.sync's new notices (D333) pass through untouched like the rest of the
body. PROTOCOL_VERSION 13 -> 14; one forward test.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

sidecar/src/main.rs

@@ -175,11 +175,19 @@ use tracing_subscriber::EnvFilter;
 /// `POST /permissions/inventory`: the plugin's whole store, in pages it sizes to the game link's
 /// line cap. Forwarded like every other object; the pages are never kept here.
 ///
+/// # Protocol 14 — the step editor (opened 2026-10-12)
+///
+/// Opened by the module's PLAN_REDESIGNS.md §2 (D332), after protocol 13 shipped with RunicNPC.
+/// One route, `POST /kits/uses`: how many of a list of players have used a kit up, or are waiting
+/// out its cooldown — counts, never a list. And `perm.sync` gains `notices`, the one-time "you
+/// earned a kit" messages (D333), with `noticesTold` in its report; both pass through untouched
+/// like the rest of that body. The first-class optional plugins (§11) join this protocol too.
+///
 /// `docs/rust-link/PROTOCOL.md` is the specification — §8 the read path, §9 identity, §10 the
 /// mirror, §11 configuration, §12 clans, §13 the raid frame, §14 the leases, §15 the world verbs,
-/// §16 the rewards, §17 the map, §18 the optional mods, §19 the walk's fixes; this constant is one
-/// of its four declaration sites.
-pub const PROTOCOL_VERSION: u32 = 13;
+/// §16 the rewards, §17 the map, §18 the optional mods, §19 the walk's fixes, §20 the step editor;
+/// this constant is one of its four declaration sites.
+pub const PROTOCOL_VERSION: u32 = 14;
 
 fn main() -> anyhow::Result<()> {
     let args = match cli::parse(std::env::args().skip(1)) {