feat(pricing): refresh catalog pricing snapshot

Add the free minimax/minimax-m3-free and minimax/minimax-m2.7-free
promotional variants (free through September 5, 2026) and
tencent/hy4-preview, drop the retired stealth/ox-alpha, and refresh the
model-id and pricing snapshots to the current 62-model catalog verified
on 2026-08-28.

tests/test-pricing.ts

@@ -27,7 +27,11 @@ const fixtureUrl = new URL("./fixtures/commandcode-model-ids.json", import.meta.
 const fixture = JSON.parse(await readFile(fixtureUrl, "utf-8")) as ModelCatalogSnapshot
 const pricingFixtureUrl = new URL("./fixtures/commandcode-pricing.json", import.meta.url)
 const pricingFixture = JSON.parse(await readFile(pricingFixtureUrl, "utf-8")) as PricingSnapshot
-const freeModels = new Set(["poolside/laguna-s-2.1-free", "stealth/ox-alpha"])
+const freeModels = new Set([
+  "poolside/laguna-s-2.1-free",
+  "minimax/minimax-m3-free",
+  "minimax/minimax-m2.7-free",
+])
 
 function assertCost(
   modelId: string,
@@ -50,7 +54,7 @@ function assertCost(
 describe("MODEL_COSTS pricing overlay", () => {
   it("covers the current Command Code model catalog snapshot", () => {
     assert.equal(fixture.source, "https://api.commandcode.ai/provider/v1/models")
-    assert.match(fixture.fetchedAt, /^2026-08-25T/)
+    assert.match(fixture.fetchedAt, /^2026-08-28T/)
 
     const catalogIds = [...fixture.modelIds].sort()
     const pricedIds = Object.keys(MODEL_COSTS).sort()
@@ -156,6 +160,12 @@ describe("MODEL_COSTS pricing overlay", () => {
       cacheRead: 0.03,
       cacheWrite: 0,
     })
+    assertCost("tencent/hy4-preview", {
+      input: 0.834,
+      output: 2.501,
+      cacheRead: 0.042,
+      cacheWrite: 0,
+    })
     assertCost("google/gemini-3.7-flash", {
       input: 0.75,
       output: 3.75,
@@ -208,7 +218,7 @@ describe("MODEL_COSTS pricing overlay", () => {
 
   it("tracks pricing provenance", () => {
     assert.equal(PRICING_SOURCE_URL, "https://commandcode.ai/docs/resources/pricing-limits")
-    assert.equal(PRICING_LAST_VERIFIED, "2026-08-25")
+    assert.equal(PRICING_LAST_VERIFIED, "2026-08-28")
   })
 
   it("fails once temporary pricing needs review", () => {