feat(writing): switch primary model to kimi k2.5, add anti-AI-slop rules to prompt

src/shared/model-requirements.test.ts

@@ -331,19 +331,23 @@ describe("CATEGORY_MODEL_REQUIREMENTS", () => {
     expect(primary.providers[0]).toBe("google")
   })
 
-  test("writing has valid fallbackChain with gemini-3-flash as primary", () => {
+  test("writing has valid fallbackChain with k2p5 as primary (kimi-for-coding)", () => {
     // given - writing category requirement
     const writing = CATEGORY_MODEL_REQUIREMENTS["writing"]
 
     // when - accessing writing requirement
-    // then - fallbackChain exists with gemini-3-flash as first entry
+    // then - fallbackChain: k2p5 → gemini-3-flash → claude-sonnet-4-5
     expect(writing).toBeDefined()
     expect(writing.fallbackChain).toBeArray()
-    expect(writing.fallbackChain.length).toBeGreaterThan(0)
+    expect(writing.fallbackChain).toHaveLength(3)
 
     const primary = writing.fallbackChain[0]
-    expect(primary.model).toBe("gemini-3-flash")
-    expect(primary.providers[0]).toBe("google")
+    expect(primary.model).toBe("k2p5")
+    expect(primary.providers[0]).toBe("kimi-for-coding")
+
+    const second = writing.fallbackChain[1]
+    expect(second.model).toBe("gemini-3-flash")
+    expect(second.providers[0]).toBe("google")
   })
 
   test("all 8 categories have valid fallbackChain arrays", () => {

src/shared/model-requirements.ts

@@ -152,10 +152,9 @@ export const CATEGORY_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
   },
   writing: {
     fallbackChain: [
+      { providers: ["kimi-for-coding"], model: "k2p5" },
       { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-flash" },
       { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-sonnet-4-5" },
-      { providers: ["zai-coding-plan"], model: "glm-4.7" },
-      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2" },
     ],
   },
 }