fix(sidecar): protocol 13 — a configuration write no longer waits for its reload (F9)

The plugin now answers config.write once the files are on disk and reports
the reload as a config.outcome event, which this process files and feeds by
its type like any other event. The reload window no longer has to fit
inside REPLY_TIMEOUT, so CONFIG_RELOAD_WINDOW and the test that asserted
the pairing are gone, and the 504 body stops pointing at a rollback.

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

sidecar/src/main.rs

@@ -101,11 +101,9 @@ use tracing_subscriber::EnvFilter;
 /// for the reload to announce itself, and **puts the old files back automatically** if it does
 /// not.
 ///
-/// Two things about that reach this process. The write is the only route here that causes a write
-/// on the game host, and it is the only one whose reply routinely spends seconds rather than
-/// milliseconds — the plugin holds the correlation open across a reload and, at worst, across a
-/// rollback as well. `web::CONFIG_RELOAD_WINDOW` is that budget, mirrored from the plugin, and a
-/// test asserts the pairing rather than trusting it.
+/// The write is the only route here that causes a write on the game host. Since protocol 13 its
+/// reply comes back as soon as the files are on disk, marked `pending`; how the reload went follows
+/// later as a `config.outcome` event, which this process files and feeds like any other.
 ///
 /// # Protocol 6 — first-party clans
 ///
@@ -165,10 +163,19 @@ use tracing_subscriber::EnvFilter;
 /// keeps it, and positions are asked for while somebody is looking and never touch the database
 /// (D111). Which layer a viewer may see is decided on the website, never here.
 ///
+/// # Protocol 13 — the first player walk's fixes
+///
+/// Opened by the configuration save (the module's PLAN_FIXES.md F9, D177): `POST /config/write`
+/// answers `pending` at once instead of holding the RPC across a reload, and the outcome arrives
+/// as a `config.outcome` event. Nothing new to route — an event is filed and fed by its `type`,
+/// whatever its kind — so what changes here is what no longer has to fit: the reload window that
+/// had to sit inside [`rpc::REPLY_TIMEOUT`] is gone.
+///
 /// `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; this constant is one of its four declaration sites.
-pub const PROTOCOL_VERSION: u32 = 12;
+/// §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;
 
 fn main() -> anyhow::Result<()> {
     let args = match cli::parse(std::env::args().skip(1)) {