Rename public group URLs to halls

skald-protocol.md

@@ -30,7 +30,7 @@ server to client direction.
 
 The client needs to know the location of the group, the (user-visible) URL
 at which the group is found.  This may be obtained either by explicit
-configuration by the user, or by parsing the `/public-groups.json` file
+configuration by the user, or by parsing the `/public-halls.json` file
 which may contain an array of group statuses (see below).
 
 A client then performs an HTTP GET request on the file `.status` at
@@ -558,7 +558,7 @@ a POST request to the authorisation server URL containing in its body
 a JSON dictionary of the following form:
 ```javascript
 {
-    "location": "https://skald.example.org/group/groupname/",
+    "location": "https://skald.example.org/hall/hallname/",
     "username": username,
     "password": password
 }
@@ -575,7 +575,7 @@ a signed JWT (a "JWS") the body of which has the following form:
 ```javascript
 {
     "sub": username,
-    "aud": "https://skald.example.org/group/groupname/",
+    "aud": "https://skald.example.org/hall/hallname/",
     "permissions": ["present"],
     "iat": now,
     "exp": now + 30s,
@@ -599,4 +599,4 @@ authentication portal performs authorisation, generates a token as above,
 then redirects back to the group's URL with the token stores in a URL
 query parameter named `token`:
 
-    https://skald.example.org/group/groupname/?token=eyJhbG...
+    https://skald.example.org/hall/hallname/?token=eyJhbG...