fix: pin release-v0.8.5 gate to constant version (was breaking on every later release) (#923)

The "docs point at the action patch" test derived `version` from the CHANGELOG's
top entry and asserted it equals "0.8.5". After 0.8.6 shipped, the top entry moved
to 0.8.6, so the assertion permanently failed — broken on main, blocking every PR
(seen on #918, #854). Only the 0.8.5 gate had this pattern.

This gate is specific to the 0.8.5 release (docs reference the patched @v0.8.5, not
the broken @v0.8.4). Pin to the constant "0.8.5" and assert that changelog entry
EXISTS rather than that it is the latest. Docs assertions unchanged (and passing).

Closes 922

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: anandgupta42

packages/opencode/test/skill/release-v0.8.5-adversarial.test.ts

@@ -228,10 +228,15 @@ describe("v0.8.5 adversarial - composite action", () => {
   })
 
   test("docs point at the action patch, not the already-published broken tag", async () => {
+    // This is the 0.8.5 release gate: it asserts the 0.8.5 docs reference the
+    // patched action tag (@v0.8.5) and NOT the already-published broken @v0.8.4.
+    // It must stay pinned to the constant "0.8.5" — earlier this derived `version`
+    // from the changelog's TOP entry, which later releases (0.8.6+) move, breaking
+    // the gate on every subsequent release. Assert the 0.8.5 entry EXISTS in the
+    // changelog rather than that it is the latest.
+    const version = "0.8.5"
     const changelog = await fs.readFile(path.join(repoRoot, "CHANGELOG.md"), "utf8")
-    // Match whether the entry is still "Unreleased" or has been date-stamped at release.
-    const version = changelog.match(/^## \[(\d+\.\d+\.\d+)\] - (?:Unreleased|\d{4}-\d{2}-\d{2})$/m)?.[1]
-    expect(version).toBe("0.8.5")
+    expect(changelog).toContain(`## [${version}]`)
 
     for (const relative of ["docs/docs/usage/dbt-pr-review.md", "github/review/examples/altimate-ingestion.yml"]) {
       const content = await fs.readFile(path.join(repoRoot, relative), "utf8")