Update wire protocol to version 7 and enhance presence management features

- Bumped the wire protocol version to 7, reflecting significant changes in the communication structure.
- Introduced a new presence message type for real-time occupancy updates, including node activity and individual presence states.
- Updated the API to include a directory endpoint for fetching short id→name mappings, improving client-side name resolution.
- Revised the map snapshot structure to be static, with people and current lessons now handled through the presence stream.
- Enhanced client-side handling of presence updates, including UI adjustments to display live occupancy and activity.
- Updated documentation to reflect the new protocol features and changes in presence management.
- Added tests to validate the new presence functionalities and ensure robust handling of real-time data.

tests/HSchool.AppHost.Tests/PeopleApiTests.cs

@@ -81,6 +81,32 @@ public class PeopleApiTests(AppHostFixture fixture)
         Assert.Empty(staff.People);
     }
 
+    [Fact]
+    public async Task Directory_ListsRosterIdsAndNames()
+    {
+        using var client = fixture.App.CreateHttpClient("server");
+        await SchoolApiTests.ResetAsync(client);
+        var school = await SchoolApiTests.CreateAsync(client, "Справочник", Start);
+
+        var directory = await client.GetFromJsonAsync<DirectoryResponse>(
+            $"/api/schools/{school.Id}/directory",
+            TestContext.Current.CancellationToken);
+        Assert.NotNull(directory);
+        Assert.NotEmpty(directory.People);
+        Assert.All(directory.People, person =>
+        {
+            Assert.False(string.IsNullOrWhiteSpace(person.Id));
+            Assert.False(string.IsNullOrWhiteSpace(person.FullName));
+        });
+
+        var page = await GetPeopleAsync(client, school.Id, "pageSize=10");
+        Assert.Contains(directory.People, person => person.Id == page.People[0].Id && person.FullName == page.People[0].FullName);
+
+        using var missing = await client.GetAsync("/api/schools/999999/directory", TestContext.Current.CancellationToken);
+        Assert.Equal(HttpStatusCode.NotFound, missing.StatusCode);
+        Assert.Equal("unknown-school", await ProblemCodeAsync(missing));
+    }
+
     [Fact]
     public async Task List_UnknownSchool_IsNotFound()
     {
@@ -204,4 +230,8 @@ public class PeopleApiTests(AppHostFixture fixture)
         IReadOnlyList<PersonRelResponse> Partners);
 
     private sealed record PersonRelResponse(string Id, string FullName, bool Female);
+
+    private sealed record DirectoryResponse(IReadOnlyList<DirectoryPersonResponse> People);
+
+    private sealed record DirectoryPersonResponse(string Id, string FullName);
 }