Add Opus 4.8 to the Claude model picker

Opus 4.8 (and its 1M-context variant) become the default Claude
models, pushing Opus 4.6 off the default slot. Opus 4.7 stays in
the list as the previous release.

packages/cli/tests/15-provider.test.ts

@@ -45,6 +45,16 @@ interface ProviderListRow {
 }
 
 const EXPECTED_CLAUDE_MODELS = [
+  {
+    id: "claude-opus-4-8[1m]",
+    model: "Opus 4.8 1M",
+    descriptionFragment: "1M context window",
+  },
+  {
+    id: "claude-opus-4-8",
+    model: "Opus 4.8",
+    descriptionFragment: "Latest release",
+  },
   {
     id: "claude-opus-4-7[1m]",
     model: "Opus 4.7 1M",
@@ -53,7 +63,7 @@ const EXPECTED_CLAUDE_MODELS = [
   {
     id: "claude-opus-4-7",
     model: "Opus 4.7",
-    descriptionFragment: "Latest release",
+    descriptionFragment: "Previous release",
   },
   {
     id: "claude-opus-4-6[1m]",

packages/server/src/server/agent/providers/claude/agent.test.ts

@@ -401,6 +401,8 @@ describe("ClaudeAgentClient.listModels", () => {
     const models = await client.listModels({ cwd: "/tmp/claude-models", force: false });
 
     expect(models.map((m) => m.id)).toEqual([
+      "claude-opus-4-8[1m]",
+      "claude-opus-4-8",
       "claude-opus-4-7[1m]",
       "claude-opus-4-7",
       "claude-opus-4-6[1m]",
@@ -416,7 +418,7 @@ describe("ClaudeAgentClient.listModels", () => {
     }
 
     const defaultModel = models.find((m) => m.isDefault);
-    expect(defaultModel?.id).toBe("claude-opus-4-6");
+    expect(defaultModel?.id).toBe("claude-opus-4-8");
   });
 });
 

packages/server/src/server/agent/providers/claude/models.test.ts

@@ -35,6 +35,8 @@ describe("getClaudeModels", () => {
   it("returns all claude models", () => {
     const models = getClaudeModels();
     expect(models.map((m) => m.id)).toEqual([
+      "claude-opus-4-8[1m]",
+      "claude-opus-4-8",
       "claude-opus-4-7[1m]",
       "claude-opus-4-7",
       "claude-opus-4-6[1m]",
@@ -49,7 +51,7 @@ describe("getClaudeModels", () => {
     const models = getClaudeModels();
     const defaults = models.filter((m) => m.isDefault);
     expect(defaults).toHaveLength(1);
-    expect(defaults[0].id).toBe("claude-opus-4-6");
+    expect(defaults[0].id).toBe("claude-opus-4-8");
   });
 
   it("returns fresh copies each call", () => {

packages/server/src/server/agent/providers/claude/models.ts

@@ -12,7 +12,7 @@ const CLAUDE_THINKING_OPTIONS = [
   { id: "max", label: "Max" },
 ] as const;
 
-const CLAUDE_OPUS_4_7_THINKING_OPTIONS = [
+const CLAUDE_OPUS_EXTENDED_THINKING_OPTIONS = [
   { id: "low", label: "Low" },
   { id: "medium", label: "Medium" },
   { id: "high", label: "High" },
@@ -21,19 +21,34 @@ const CLAUDE_OPUS_4_7_THINKING_OPTIONS = [
 ] as const;
 
 const CLAUDE_MODELS: AgentModelDefinition[] = [
+  {
+    provider: "claude",
+    id: "claude-opus-4-8[1m]",
+    label: "Opus 4.8 1M",
+    description: "Opus 4.8 with 1M context window",
+    thinkingOptions: [...CLAUDE_OPUS_EXTENDED_THINKING_OPTIONS],
+  },
+  {
+    provider: "claude",
+    id: "claude-opus-4-8",
+    label: "Opus 4.8",
+    description: "Opus 4.8 · Latest release",
+    isDefault: true,
+    thinkingOptions: [...CLAUDE_OPUS_EXTENDED_THINKING_OPTIONS],
+  },
   {
     provider: "claude",
     id: "claude-opus-4-7[1m]",
     label: "Opus 4.7 1M",
     description: "Opus 4.7 with 1M context window",
-    thinkingOptions: [...CLAUDE_OPUS_4_7_THINKING_OPTIONS],
+    thinkingOptions: [...CLAUDE_OPUS_EXTENDED_THINKING_OPTIONS],
   },
   {
     provider: "claude",
     id: "claude-opus-4-7",
     label: "Opus 4.7",
-    description: "Opus 4.7 · Latest release",
+    description: "Opus 4.7 · Previous release",
-    thinkingOptions: [...CLAUDE_OPUS_4_7_THINKING_OPTIONS],
+    thinkingOptions: [...CLAUDE_OPUS_EXTENDED_THINKING_OPTIONS],
   },
   {
     provider: "claude",
@@ -47,7 +62,6 @@ const CLAUDE_MODELS: AgentModelDefinition[] = [
     id: "claude-opus-4-6",
     label: "Opus 4.6",
     description: "Opus 4.6 · Most capable for complex work",
-    isDefault: true,
     thinkingOptions: [...CLAUDE_THINKING_OPTIONS],
   },
   {