feat: presence on tickets

A ticket's page beats every 10 s (touchPresence / PUT
/issues/{issue}/presence, with whether I am editing) and gets back who
else is there, editing ones first. Entries live in Redis, one hash per
ticket, and fade after 30 s without a beat; leaving the page takes me out
at once. Only for people who can read the ticket; never in the event
store. The ticket shows «Bob está editando · Ana también lo está viendo»
above its title; editing means a ticket or comment form is open or a
comment is being written.

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

libs/web/tracker/infrastructure/src/lib/adapters/graphql-presence.gateway.ts

@@ -0,0 +1,25 @@
+import { inject, Injectable } from '@angular/core';
+import { Presence, PresenceGateway } from '@task-stream/web/tracker/domain';
+import { map, Observable } from 'rxjs';
+import {
+  LeavePresenceDocument,
+  TouchPresenceDocument,
+} from '../graphql/generated';
+import { GraphqlOperations } from './graphql-operations';
+
+@Injectable()
+export class GraphqlPresenceGateway extends PresenceGateway {
+  private readonly gql = inject(GraphqlOperations);
+
+  touch(issueId: string, editing: boolean): Observable<Presence[]> {
+    return this.gql
+      .mutate(TouchPresenceDocument, { issueId, editing })
+      .pipe(map((d) => d.touchPresence));
+  }
+
+  leave(issueId: string): Observable<void> {
+    return this.gql
+      .mutate(LeavePresenceDocument, { issueId })
+      .pipe(map(() => undefined));
+  }
+}

libs/web/tracker/infrastructure/src/lib/graphql/generated.ts

@@ -1546,6 +1546,25 @@ export type NotificationAddedSubscription = {
   };
 };
 
+export type TouchPresenceMutationVariables = Exact<{
+  issueId: string;
+  editing: boolean;
+}>;
+
+export type TouchPresenceMutation = {
+  touchPresence: Array<{
+    editing: boolean;
+    at: string;
+    user: { id: string; name: string };
+  }>;
+};
+
+export type LeavePresenceMutationVariables = Exact<{
+  issueId: string;
+}>;
+
+export type LeavePresenceMutation = { leavePresence: boolean };
+
 export type MyProjectsQueryVariables = Exact<{ [key: string]: never }>;
 
 export type MyProjectsQuery = {
@@ -9536,6 +9555,153 @@ export const NotificationAddedDocument = {
   NotificationAddedSubscription,
   NotificationAddedSubscriptionVariables
 >;
+export const TouchPresenceDocument = {
+  kind: 'Document',
+  definitions: [
+    {
+      kind: 'OperationDefinition',
+      operation: 'mutation',
+      name: { kind: 'Name', value: 'TouchPresence' },
+      variableDefinitions: [
+        {
+          kind: 'VariableDefinition',
+          variable: {
+            kind: 'Variable',
+            name: { kind: 'Name', value: 'issueId' },
+          },
+          type: {
+            kind: 'NonNullType',
+            type: { kind: 'NamedType', name: { kind: 'Name', value: 'ID' } },
+          },
+        },
+        {
+          kind: 'VariableDefinition',
+          variable: {
+            kind: 'Variable',
+            name: { kind: 'Name', value: 'editing' },
+          },
+          type: {
+            kind: 'NonNullType',
+            type: {
+              kind: 'NamedType',
+              name: { kind: 'Name', value: 'Boolean' },
+            },
+          },
+        },
+      ],
+      selectionSet: {
+        kind: 'SelectionSet',
+        selections: [
+          {
+            kind: 'Field',
+            name: { kind: 'Name', value: 'touchPresence' },
+            arguments: [
+              {
+                kind: 'Argument',
+                name: { kind: 'Name', value: 'issueId' },
+                value: {
+                  kind: 'Variable',
+                  name: { kind: 'Name', value: 'issueId' },
+                },
+              },
+              {
+                kind: 'Argument',
+                name: { kind: 'Name', value: 'editing' },
+                value: {
+                  kind: 'Variable',
+                  name: { kind: 'Name', value: 'editing' },
+                },
+              },
+            ],
+            selectionSet: {
+              kind: 'SelectionSet',
+              selections: [
+                {
+                  kind: 'Field',
+                  name: { kind: 'Name', value: 'user' },
+                  selectionSet: {
+                    kind: 'SelectionSet',
+                    selections: [
+                      {
+                        kind: 'FragmentSpread',
+                        name: { kind: 'Name', value: 'UserRefFields' },
+                      },
+                    ],
+                  },
+                },
+                { kind: 'Field', name: { kind: 'Name', value: 'editing' } },
+                { kind: 'Field', name: { kind: 'Name', value: 'at' } },
+              ],
+            },
+          },
+        ],
+      },
+    },
+    {
+      kind: 'FragmentDefinition',
+      name: { kind: 'Name', value: 'UserRefFields' },
+      typeCondition: {
+        kind: 'NamedType',
+        name: { kind: 'Name', value: 'UserRef' },
+      },
+      selectionSet: {
+        kind: 'SelectionSet',
+        selections: [
+          { kind: 'Field', name: { kind: 'Name', value: 'id' } },
+          { kind: 'Field', name: { kind: 'Name', value: 'name' } },
+        ],
+      },
+    },
+  ],
+} as unknown as DocumentNode<
+  TouchPresenceMutation,
+  TouchPresenceMutationVariables
+>;
+export const LeavePresenceDocument = {
+  kind: 'Document',
+  definitions: [
+    {
+      kind: 'OperationDefinition',
+      operation: 'mutation',
+      name: { kind: 'Name', value: 'LeavePresence' },
+      variableDefinitions: [
+        {
+          kind: 'VariableDefinition',
+          variable: {
+            kind: 'Variable',
+            name: { kind: 'Name', value: 'issueId' },
+          },
+          type: {
+            kind: 'NonNullType',
+            type: { kind: 'NamedType', name: { kind: 'Name', value: 'ID' } },
+          },
+        },
+      ],
+      selectionSet: {
+        kind: 'SelectionSet',
+        selections: [
+          {
+            kind: 'Field',
+            name: { kind: 'Name', value: 'leavePresence' },
+            arguments: [
+              {
+                kind: 'Argument',
+                name: { kind: 'Name', value: 'issueId' },
+                value: {
+                  kind: 'Variable',
+                  name: { kind: 'Name', value: 'issueId' },
+                },
+              },
+            ],
+          },
+        ],
+      },
+    },
+  ],
+} as unknown as DocumentNode<
+  LeavePresenceMutation,
+  LeavePresenceMutationVariables
+>;
 export const MyProjectsDocument = {
   kind: 'Document',
   definitions: [

libs/web/tracker/infrastructure/src/lib/graphql/presence.graphql

@@ -0,0 +1,13 @@
+mutation TouchPresence($issueId: ID!, $editing: Boolean!) {
+  touchPresence(issueId: $issueId, editing: $editing) {
+    user {
+      ...UserRefFields
+    }
+    editing
+    at
+  }
+}
+
+mutation LeavePresence($issueId: ID!) {
+  leavePresence(issueId: $issueId)
+}

libs/web/tracker/infrastructure/src/lib/tracker-infrastructure.providers.ts

@@ -10,6 +10,7 @@ import {
   IssuesGateway,
   NotificationsGateway,
   CalendarGateway,
+  PresenceGateway,
   PushDevice,
   ProjectsGateway,
   ReleasesGateway,
@@ -31,6 +32,7 @@ import {
 import { GraphqlIssuesGateway } from './adapters/graphql-issues.gateway';
 import { GraphqlNotificationsGateway } from './adapters/graphql-notifications.gateway';
 import { GraphqlCalendarGateway } from './adapters/graphql-calendar.gateway';
+import { GraphqlPresenceGateway } from './adapters/graphql-presence.gateway';
 import { BrowserPushDevice } from './adapters/browser-push.device';
 import { HttpAttachmentsGateway } from './adapters/http-attachments.gateway';
 import { HttpProposalsGateway } from './adapters/http-proposals.gateway';
@@ -56,6 +58,7 @@ export function provideTrackerInfrastructure(): EnvironmentProviders {
     { provide: UsersGateway, useClass: GraphqlUsersGateway },
     { provide: NotificationsGateway, useClass: GraphqlNotificationsGateway },
     { provide: CalendarGateway, useClass: GraphqlCalendarGateway },
+    { provide: PresenceGateway, useClass: GraphqlPresenceGateway },
     { provide: PushDevice, useClass: BrowserPushDevice },
     { provide: TrackerRealtimeGateway, useClass: GraphqlRealtimeGateway },
     { provide: SavedFiltersGateway, useClass: GraphqlSavedFiltersGateway },