[nazarli-shabnam]

Closes #5389

Problem

Clicking edit on a maintenance rule runs router.replace(/maintenance?cel=${rule.cel_query}) with the raw CEL query. Characters such as &&, == and # are not URL-encoded, so the query string is cut off and the CEL does not come through for complex expressions. This is the first bug in #5389.

Fix

maintenance.tsx wraps the query in encodeURIComponent, as other pages that link with a cel parameter already do (for example service-node.tsx).

Tests

Added app/(keep)/maintenance/__tests__/maintenance.test.tsx: it opens a rule whose CEL contains ==, && and quotes through the table's editCallback and expects router.replace to receive the encoded URL.

Run with npx jest in a throwaway node:22-slim container after npm ci --ignore-scripts from the repo lockfile. Before the fix it failed (received the raw name == "Disk" && ...); after the fix it passed. Prettier 3.5.3 --check passes on both files.

Not verified

• No browser check. I did not confirm that the form in the issue now shows the full CEL, only that the URL is encoded.
• The issue also reports that the edit form does not show the CEL and asks for extra URL parameters (name, description, status, start time). I did not touch those; they look like separate changes, so this PR may fix only part of the report.
• I did not run next lint, tsc or e2e tests.

AI disclosure

Claude (Anthropic) helped investigate the bug and draft the change and this description. I reviewed the diff.