Server: wire ProfileService so access tokens carry the name claim

The custom ProfileService (Yavsc.Services.ProfileService) was never
registered with IdentityServer, so IS8 fell back to its default
profile service — which only emits claims listed in each API
resource's UserClaims (RequestedClaimTypes). "name" was never among
them, so every access token lacked "name" and GetUserName() resolved
to null on all bearer resource hosts (Blogs/Api): the MyFiles upload
500 and the unreachable User.Identity.Name. The class was dead code;
all prior tweaks to it (FullName→UserName) and to ServiceExtensions
(MapInboundClaims=false) were necessary but insufficient until it was
actually wired in.

- HostingExtensions: AddProfileService<ProfileService>() after
  AddAspNetIdentity<ApplicationUser>().
- ProfileService: emit name=user.UserName, email, roles for any user
  grant whose client has "profile" in AllowedScopes, independent of
  the caller (the old ParsedScopes gate only fired for the id-token
  caller, never the access-token caller).
- ServiceExtensions: JwtBearer NameClaimType=JwtClaimTypes.Name,
  MapInboundClaims=false (keep short claim names as-emitted).
- FileSystemHelpers: EnsureDestinationDirectory uses GetUserName()
  (the "name" claim) instead of User.Identity.Name for the per-user
  storage root.

Tests:
- TestTokenIssuer: stamp a "name" claim = subject so test tokens mirror
  production shape (fixes FileSystemApiTests upload 500).
- Remoting: PasswordToken_carries_name_claim_equal_to_login mints a
  real JWT via the IS token endpoint (password grant, openid profile)
  and asserts the access token carries name=login and GetUserName()
  resolves to it.
- WebServerFixture: AccessTokenType=0 (Jwt in IS8; 1=Reference, the
  inverse of Duende); allow openid+profile on the test client; re-seed
  the openid/profile identity resources in ReseedAuthTestData (a
  ResetAndMigrateDatabase wipes the shared in-memory store and previously
  left them gone → invalid_scope).
- BillingServiceTests: [Collection("Yavsc Server")] to serialize with
  the host build that mutates the static BillingService/Config
  registries (pre-existing parallel race that the new test's timing
  surfaced).

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

src/Yavsc.Org.Tests/NonRegression/BillingServiceTests.cs

@@ -8,6 +8,16 @@ using Xunit;
 
 namespace Yavsc
 {
+    // BillingService and Config expose static mutable registries that
+    // WorkflowHelpers.ConfigureBillingService() also mutates from the
+    // WebServerFixture host build (HostingExtensions.cs). Without a
+    // collection, xUnit runs this class in parallel with the
+    // "Yavsc Server" collection, and the host build's ConfigureBilling
+    // call can land between this test's two ConfigureBilling calls,
+    // breaking the idempotency count assertion (a flaky failure that
+    // surfaces whenever the fixture's timing shifts). Pinning the class
+    // to the same collection serializes it with the host build.
+    [Collection("Yavsc Server")]
     [Trait("regression", "II")]
     public class BillingServiceTests
     {