Bump indirect Go module github.com/dlclark/regexp2/v2 from v2.5.1 to v2.5.2 via go get -u ./... and go mod tidy.

All other dependency manifests are already current: cli/dashboard and cli/go.mod direct deps were upgraded in #516, web and cli/package.json npm upgrades are all within the 7-day release-age cooldown, and TypeScript is held at the latest 6.0.x (7.x is blocked by typescript-eslint).

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>