Providers: skip context1m beta for Anthropic OAuth tokens (#24620)

* Providers: skip context1m beta for Anthropic OAuth tokens

* Tests: cover OAuth context1m beta skip behavior

* Docs: note context1m OAuth incompatibility

* Agents: add context1m-aware context token resolver

* Agents: cover context1m context-token resolver

* Commands: apply context1m-aware context tokens in session store

* Commands: apply context1m-aware context tokens in status summary

* Status: resolve context tokens with context1m model params

* Status: test context1m status context display

src/agents/context.test.ts

@@ -1,5 +1,10 @@
 import { describe, expect, it } from "vitest";
-import { applyConfiguredContextWindows, applyDiscoveredContextWindows } from "./context.js";
+import {
+  ANTHROPIC_CONTEXT_1M_TOKENS,
+  applyConfiguredContextWindows,
+  applyDiscoveredContextWindows,
+  resolveContextTokensForModel,
+} from "./context.js";
 import { createSessionManagerRuntimeRegistry } from "./pi-extensions/session-manager-runtime-registry.js";
 
 describe("applyDiscoveredContextWindows", () => {
@@ -75,3 +80,47 @@ describe("createSessionManagerRuntimeRegistry", () => {
     expect(registry.get(123)).toBeNull();
   });
 });
+
+describe("resolveContextTokensForModel", () => {
+  it("returns 1M context when anthropic context1m is enabled for opus/sonnet", () => {
+    const result = resolveContextTokensForModel({
+      cfg: {
+        agents: {
+          defaults: {
+            models: {
+              "anthropic/claude-opus-4-6": {
+                params: { context1m: true },
+              },
+            },
+          },
+        },
+      },
+      provider: "anthropic",
+      model: "claude-opus-4-6",
+      fallbackContextTokens: 200_000,
+    });
+
+    expect(result).toBe(ANTHROPIC_CONTEXT_1M_TOKENS);
+  });
+
+  it("does not force 1M context for non-opus/sonnet Anthropic models", () => {
+    const result = resolveContextTokensForModel({
+      cfg: {
+        agents: {
+          defaults: {
+            models: {
+              "anthropic/claude-haiku-3-5": {
+                params: { context1m: true },
+              },
+            },
+          },
+        },
+      },
+      provider: "anthropic",
+      model: "claude-haiku-3-5",
+      fallbackContextTokens: 200_000,
+    });
+
+    expect(result).toBe(200_000);
+  });
+});