Rename replay → initChannelState

Rename the query parameter, function, and all related comments
from 'replay' to 'initChannelState' to better reflect the
semantics: the server initializes channel state for the
reconnecting client rather than replaying past events.

README.md

@@ -1070,7 +1070,7 @@ curl -s http://localhost:8080/api/v1/state \
   -H "Authorization: Bearer $TOKEN" | jq .
 ```
 
-**Reconnect with channel state init:**
+**Reconnect with channel state initialization:**
 ```bash
 curl -s "http://localhost:8080/api/v1/state?initChannelState=1" \
   -H "Authorization: Bearer $TOKEN" | jq .

internal/handlers/api.go

@@ -445,10 +445,10 @@ func (hdlr *Handlers) enqueueNumeric(
 
 // HandleState returns the current session's info and
 // channels.  When called with ?initChannelState=1, it also
-// enqueues synthetic JOIN + TOPIC + NAMES messages for every
-// channel the session belongs to so that a reconnecting
-// client can rebuild its channel tabs from the message
-// stream.
+// enqueues synthetic JOIN + TOPIC + NAMES messages for
+// every channel the session belongs to so that a
+// reconnecting client can rebuild its channel tabs from
+// the message stream.
 func (hdlr *Handlers) HandleState() http.HandlerFunc {
 	return func(
 		writer http.ResponseWriter,

internal/handlers/auth.go

@@ -182,8 +182,8 @@ func (hdlr *Handlers) handleLogin(
 		request, clientID, sessionID, payload.Nick,
 	)
 
-	// Init channel state so the new client knows which
-	// channels the session already belongs to.
+	// Initialize channel state so the new client knows
+	// which channels the session already belongs to.
 	hdlr.initChannelState(
 		request, clientID, sessionID, payload.Nick,
 	)

web/src/app.jsx

@@ -335,7 +335,7 @@ function App() {
           if (msg.to) addMessage(msg.to, { ...base, text, system: true });
           if (msg.to && msg.to.startsWith("#")) {
             // Create a tab when the current user joins a channel
-            // (including initial JOINs on reconnect).
+            // (including JOINs from initChannelState on reconnect).
             if (msg.from === nickRef.current) {
               setTabs((prev) => {
                 if (
@@ -656,9 +656,10 @@ function App() {
       if (isResumed) {
         // Request MOTD on resumed sessions (new sessions
         // get it automatically from the server during
-        // creation).  Channel state is initialised by the
-        // server via the message queue (?initChannelState=1), so we
-        // do not need to re-JOIN channels here.
+        // creation).  Channel state is initialized by the
+        // server via the message queue
+        // (?initChannelState=1), so we do not need to
+        // re-JOIN channels here.
         try {
           await api("/messages", {
             method: "POST",