chore: update GPT-5.2 references to GPT-5.4

Align runtime defaults, tests, docs, and generated artifacts with the newer GPT-5.4 baseline. Keep think-mode and prompt-routing expectations consistent after the model version bump.

src/shared/model-requirements.test.ts

@@ -7,19 +7,19 @@ import {
 } from "./model-requirements"
 
 describe("AGENT_MODEL_REQUIREMENTS", () => {
-  test("oracle has valid fallbackChain with gpt-5.2 as primary", () => {
+  test("oracle has valid fallbackChain with gpt-5.4 as primary", () => {
     // given - oracle agent requirement
     const oracle = AGENT_MODEL_REQUIREMENTS["oracle"]
 
     // when - accessing oracle requirement
-    // then - fallbackChain exists with gpt-5.2 as first entry
+    // then - fallbackChain exists with gpt-5.4 as first entry
     expect(oracle).toBeDefined()
     expect(oracle.fallbackChain).toBeArray()
     expect(oracle.fallbackChain.length).toBeGreaterThan(0)
 
     const primary = oracle.fallbackChain[0]
     expect(primary.providers).toContain("openai")
-    expect(primary.model).toBe("gpt-5.2")
+    expect(primary.model).toBe("gpt-5.4")
     expect(primary.variant).toBe("high")
   })
 
@@ -435,7 +435,7 @@ describe("ModelRequirement type", () => {
     const requirement: ModelRequirement = {
       fallbackChain: [
         { providers: ["anthropic", "github-copilot"], model: "claude-opus-4-6", variant: "max" },
-        { providers: ["openai", "github-copilot"], model: "gpt-5.2", variant: "high" },
+        { providers: ["openai", "github-copilot"], model: "gpt-5.4", variant: "high" },
       ],
     }
 
@@ -444,7 +444,7 @@ describe("ModelRequirement type", () => {
     expect(requirement.fallbackChain).toBeArray()
     expect(requirement.fallbackChain).toHaveLength(2)
     expect(requirement.fallbackChain[0].model).toBe("claude-opus-4-6")
-    expect(requirement.fallbackChain[1].model).toBe("gpt-5.2")
+    expect(requirement.fallbackChain[1].model).toBe("gpt-5.4")
   })
 
   test("ModelRequirement variant is optional", () => {