feat: adopt smolmail protocol 1.1 with accept tokens and leave-mail-on-server

test/e2e.py

@@ -85,12 +85,18 @@ def main() -> int:
         run(bob + ["register", f"bob@{host}"])
         check("bob registers on the reference server", True)
 
-        # --- reference client sends to the JS client
+        # bob needs alice as a known contact before he can accept her (§5.8).
+        run(bob + ["resolve", f"alice@{host}"])
+
+        # --- reference client sends to the JS client, unsolicited: bob has not
+        # accepted alice yet, so it lands in his requests tier, not the main one
         run(alice + ["send", f"bob@{host}", "--subject", "greetings", "--body", "hello bob"])
         print(run(bob + ["fetch"]).strip())
-        bob_list = run(bob + ["list"])
-        check("bob lists alice's message", "greetings" in bob_list, bob_list)
-        bob_read = run(bob + ["read", re.match(r"([0-9a-f]{8})", bob_list).group(1)])
+        bob_requests = run(bob + ["list", "--requests"])
+        check("bob's requests tier holds alice's unsolicited message", "greetings" in bob_requests,
+              bob_requests)
+        check("bob's main tier is still empty", "greetings" not in run(bob + ["list"]))
+        bob_read = run(bob + ["read", re.match(r"([0-9a-f]{8})", bob_requests).group(1)])
         alice_pub = re.search(r"public key:  (\S+)", run(alice + ["whoami"])).group(1)
         check("bob reads the message", "hello bob" in bob_read, bob_read)
         check("bob sees alice's key", alice_pub in bob_read)
@@ -99,23 +105,34 @@ def main() -> int:
         check("reference client emits the signed reply address",
               "reply-to: smol://alice@" in bob_read, bob_read)
 
-        # --- JS client replies, through the bridge's WebSocket relay
+        # --- bob accepts alice (§5.8): pushed to the server right away, so her
+        # future mail reaches his main tier
+        accepted = run(bob + ["accept", f"alice@{host}"])
+        check("bob's server now holds an accept token", "server now holds 1 accept token" in accepted,
+              accepted)
+
+        # --- JS client replies, through the bridge's WebSocket relay. Bob has
+        # accepted alice, so this carries the token issued to her — but it is
+        # still unsolicited from alice's side, landing in her requests tier.
         ws_env = dict(os.environ, GSMOL_TRANSPORT="ws", GSMOL_BRIDGE=f"ws://127.0.0.1:{bridge_port}")
         reply_id = re.search(r"sent ([0-9a-f]+)", run(bob + ["send", f"alice@{host}",
                        "--subject", "re: greetings", "--body", "hello alice"], env=ws_env)).group(1)
         check("bob sends through the bridge", bool(reply_id))
         run(alice + ["fetch"])
-        alice_list = run(alice + ["list"])
-        check("alice lists bob's reply", "re: greetings" in alice_list, alice_list)
+        alice_requests = run(alice + ["list", "--requests"])
+        check("alice's requests tier holds bob's reply", "re: greetings" in alice_requests,
+              alice_requests)
         alice_read = run(alice + ["read", reply_id[:8]])
         check("alice reads bob's reply", "hello alice" in alice_read, alice_read)
         check("reference client verifies the JS signature", "signature verified" in alice_read)
         # bob's reply carries his signed smol:// address; a receiver that does
         # not know the field must still preserve and display it (SPEC.md §5.5)
         check("reference client preserves the signed reply address",
-              "reply-to:smol://bob@" in alice_read, alice_read)
+              bool(re.search(r"reply-to:\s+smol://bob@", alice_read)), alice_read)
 
-        # --- rotation: the JS client rotates, the reference client walks the chain
+        # --- having now learned bob's accept token from that reply's Accept
+        # field, alice's next message to him carries a matching MAC and
+        # reaches his main tier even after he rotates his key
         bob_rotated = run(bob + ["rotate"])
         new_key = re.search(r"new key:     (\S+)", bob_rotated).group(1)
         resolved = run(alice + ["resolve", f"bob@{host}"])
@@ -124,7 +141,8 @@ def main() -> int:
                      "--anonymous"])
         print(run(bob + ["fetch"]).strip())
         bob_list = run(bob + ["list"])
-        check("bob reads mail addressed to the new key", "post-rotation" in bob_list)
+        check("bob's main tier reaches mail addressed to the new key", "post-rotation" in bob_list,
+              bob_list)
         # --anonymous omits the reply address; the field list must show none
         post_read = run(bob + ["read", re.search(r"([0-9a-f]{8})  .*post-rotation",
                                                  bob_list).group(1)])