feat: conversations on a ticket are settled, and you see who is typing

A top-level comment and its replies can be resolved by whoever can
change the ticket (CommentThreadResolvedEvent), with an optional
conclusion added as a reply marked as a decision, so it shows above the
ticket. A settled conversation folds to one line (topic, who settled it
and the conclusion) and can be unfolded or reopened; the header counts
the open ones, and finishing the ticket with one open asks first.

«Ana está escribiendo…» shows in the conversation being answered, at
once: a `typing` mutation publishes to a Redis channel per ticket
(`typing` subscription), never stored. In replies, Enter sends and
Shift+Enter breaks the line, except inside lists and code.

API: resolveThread / PUT-DELETE /api/comments/{id}/resolution, Comment
.resolved/resolvedBy/resolvedAt, typing mutation and subscription. MCP:
resolve_thread.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libs/web/tracker/application/src/lib/events/issue.events.ts

@@ -81,6 +81,11 @@ export const issuePageEvents = eventGroup({
     commentEditRequested: type<{ commentId: string; body: string }>(),
     reactRequested: type<{ commentId: string; emoji: string; on: boolean }>(),
     decisionRequested: type<{ commentId: string; on: boolean }>(),
+    threadResolveRequested: type<{
+      commentId: string;
+      resolved: boolean;
+      conclusion: string | null;
+    }>(),
     voteRequested: type<{ issueId: string; on: boolean }>(),
     /** An image pasted into a text was uploaded (it joins the ticket's files). */
     imagePasted: type<{ issueId: string }>(),

libs/web/tracker/application/src/lib/events/presence.events.ts

@@ -1,12 +1,14 @@
 import { type } from '@ngrx/signals';
 import { eventGroup } from '@ngrx/signals/events';
-import { Presence } from '@task-stream/web/tracker/domain';
+import { Presence, Typing } from '@task-stream/web/tracker/domain';
 
 export const presencePageEvents = eventGroup({
   source: 'Issue Presence',
   events: {
     opened: type<string>(),
     editingChanged: type<boolean>(),
+    /** I typed in an answer to this conversation (null: a new comment). */
+    typed: type<string | null>(),
     left: type<void>(),
   },
 });
@@ -15,5 +17,9 @@ export const presenceApiEvents = eventGroup({
   source: 'Presence API',
   events: {
     seen: type<Presence[]>(),
+    /** Someone else is writing. */
+    typing: type<Typing>(),
+    /** …and stopped a while ago (the `at` it was last seen). */
+    typingStopped: type<{ userId: string; at: string }>(),
   },
 });