Implement CHATHISTORY subcommands, TOPIC events, REDACT cap filter

Major chathistory work:
- Add CHATHISTORY BEFORE/AFTER/BETWEEN/AROUND with msgid/timestamp anchors
- Filter redacted messages from history per spec
- Persist TOPIC events for event-playback support
- Use historical timestamps in CHATHISTORY responses
- Support DM history queries (msg-to-self and between users)
- Add draft/event-playback capability

REDACT improvements:
- Only deliver REDACT to clients with draft/message-redaction cap
- Add msgid/time tags to generic TAGMSG handler
- FAIL responses include subcommand context per spec

Tag-line refactoring:
- Add tag-line-at helper for stored event timestamps
- Share msg-at between event store and broadcast in PRIVMSG/TOPIC
- Use ISO time with explicit Date instead of double iso-time call

1 files changed, 3 insertions, 1 deletions

diff --git a/tests/unit.clj b/tests/unit.clj
index 687c91f..fad96fc 100644
--- a/tests/unit.clj
+++ b/tests/unit.clj
@@ -1536,10 +1536,12 @@
   (testing "REDACT deletes and notifies (draft/message-redaction)"
     (let [alice-out (java.io.ByteArrayOutputStream.)
           bob-out   (java.io.ByteArrayOutputStream.)
+          bob-atom  (atom {:caps #{"draft/message-redaction"}})
           {:keys [test-network-id] :as components}
           (assoc (test-components-with-network)
             :clients  (atom {"alice" {:w alice-out}
-                             "bob"   {:w bob-out}})
+                             "bob"   {:w bob-out
+                                      :client-atom bob-atom}})
             :channels (atom {}))
           conn  (:conn components)
           alice (registered-client "alice" alice-out test-network-id)]