Update Known Issues: Anthropic binding gap is mitigated, not open

Author: NinjaRocks

README.md

@@ -139,7 +139,7 @@ CI catches build-level drift but not all runtime regressions. For the model-ID s
 
 ## Known issues
 
-- **`Anthropic.SDK` 5.10 ↔ `Microsoft.Extensions.AI` 10.5 binding gap.** `Anthropic.SDK` 5.10.0 is compiled against `Microsoft.Extensions.AI.Abstractions` 10.3.0; the central pin moved to 10.5.0 (required by `Microsoft.Agents.AI` 1.3), which reshapes `HostedMcpServerTool.AuthorizationToken`. Calling Claude through Anthropic.SDK's `IChatClient` bridge therefore throws `MissingMethodException` at runtime. This affects `samples/ch04-agent-framework/04.2.4-anthropic-agents` -- it builds clean but does not run as-shipped. The throwaway harness at `tests/AnthropicVerification/` works because it has no `Microsoft.Agents.AI` dependency and pins M.E.AI to 10.3.0 locally via `VersionOverride`; the same override does **not** work on the chapter sample because Agents.AI 1.3 itself rejects 10.3 with `CS1705`. Mitigation paths and pre-print decision are tracked in `docs/verification-log.md` (entry `2026-05-02`). Likely cleared once `Anthropic.SDK` 5.11+ ships rebuilt against M.E.AI 10.5+.
+- **`Anthropic.SDK` 5.10 ↔ `Microsoft.Extensions.AI` 10.5 binding gap (mitigated).** `Anthropic.SDK` 5.10.0 is compiled against `Microsoft.Extensions.AI.Abstractions` 10.3.0; the central pin is 10.5.0 (required by `Microsoft.Agents.AI` 1.3), which reshapes `HostedMcpServerTool.AuthorizationToken`. Calling Claude through Anthropic.SDK's bundled `IChatClient` bridge therefore throws `MissingMethodException` at runtime against the central pins. **Mitigation (2026-05-03):** `samples/ch04-agent-framework/04.2.4-anthropic-agents` ships a thin local adapter, `AnthropicChatClient.cs`, that calls `AnthropicClient.Messages.GetClaudeMessageAsync` directly and translates Anthropic ↔ M.E.AI types itself, bypassing the broken `ChatClientHelper`. The sample builds clean and runs end-to-end (two-turn live conversation confirmed against `claude-haiku-4-5-20251001`). The throwaway harness at `tests/AnthropicVerification/` is unaffected -- it has no `Microsoft.Agents.AI` dependency and keeps a local `VersionOverride` to M.E.AI 10.3.0. **Cleanup:** once `Anthropic.SDK` 5.11+ ships rebuilt against M.E.AI 10.5+, delete `AnthropicChatClient.cs`, revert `Program.cs` to `IChatClient chat = new AnthropicClient(apiKey).Messages;`, drop the `VersionOverride` on the verification harness, and re-run both. Full chain in `docs/verification-log.md` (entries `2026-05-02` and `2026-05-03`).
 
 ## Versioning and tags