fix(ci): fix remaining CI failures

- alembic.ini: change fallback DB to tod_test (CI creates tod_test, not tod)
- ci.yml: upgrade Go to 1.25 (matches go.mod)
- ci.yml: upgrade Node to 20 (fixes ESM require() error in Vitest)
- conftest.py: ruff format

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.github/workflows/ci.yml

@@ -42,7 +42,7 @@ jobs:
 
       - uses: actions/setup-go@v5
         with:
-          go-version: "1.24"
+          go-version: "1.25"
 
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v6
@@ -57,7 +57,7 @@ jobs:
 
       - uses: actions/setup-node@v4
         with:
-          node-version: "18"
+          node-version: "20"
           cache: "npm"
           cache-dependency-path: frontend/package-lock.json
 
@@ -183,7 +183,7 @@ jobs:
 
       - uses: actions/setup-go@v5
         with:
-          go-version: "1.24"
+          go-version: "1.25"
 
       - uses: actions/cache@v4
         with:
@@ -203,7 +203,7 @@ jobs:
 
       - uses: actions/setup-node@v4
         with:
-          node-version: "18"
+          node-version: "20"
           cache: "npm"
           cache-dependency-path: frontend/package-lock.json