chore(quality): drop two stale ESLint suppression entries

#12653 and #12358 fixed the violations these covered but left the entries
behind, and eslint treats a suppression with nothing left to suppress as an
error. That blocks the pre-commit hook on any commit whose staged set
includes either file.

- open-sse/services/imageCombo.ts (no-unused-vars)
- tests/unit/chat-helpers.test.ts (no-explicit-any)

A ratchet tightening, not a rebaseline: both counts go to zero by deletion.
The three no-explicit-any errors remaining in
tests/unit/volcengine-plan-binding-upsert.test.ts are untouched here — that
is the pre-existing base-red #13215 tracks.

changelog.d/maintenance/stale-eslint-suppressions-20260911.md

@@ -0,0 +1 @@
+- **chore(quality):** drop two ESLint suppression entries whose violations no longer exist, so `eslint --suppressions-location` stops rejecting every commit that touches the surrounding files

config/quality/eslint-suppressions.json

@@ -568,11 +568,6 @@
       "count": 1
     }
   },
-  "open-sse/services/imageCombo.ts": {
-    "@typescript-eslint/no-unused-vars": {
-      "count": 1
-    }
-  },
   "open-sse/services/inAppLoginService.ts": {
     "@typescript-eslint/no-explicit-any": {
       "count": 2
@@ -2806,11 +2801,6 @@
       "count": 10
     }
   },
-  "tests/unit/chat-helpers.test.ts": {
-    "@typescript-eslint/no-explicit-any": {
-      "count": 13
-    }
-  },
   "tests/unit/chat-rate-limit-body-lock.test.ts": {
     "@typescript-eslint/no-explicit-any": {
       "count": 2