chore: update dependencies (2026-09-11)

[majabojarska]

• Updates tools and pkgs. Tools ship Golang 1.27
  • this required bumping golangci-lint, which shipped a new staticcheck (0.7.0 -> 0.8.1). staticcheck 0.8.0 starts flagging the use of deprecated fields as SA1019. This caused a lot of new linter flags in the Talos legacy config tests, where we intentionally reference deprecated fields to test for backward compatibility. I think that moving forward it's useful to have stricter linting for usage of deprecated symbols, so this diff ignores the pre-existing references to deprecated struct fields. Afaik there's no way to ignore this on a config level, if we wanted to, as both deprecated functions and struct fields are bundled together under one check (SA1019).
  • Regarding the meta_test.go, expectedGzippedSize - Go 1.27 compress/flate emits 4 fewer bytes for this input than the previous toolchain. Roundtrip test (encode->decode) still results in the same data as input.
• Updates Helm and Cilium CLI.
• Updates helm charts in k8s integration tests.
• Updates the Dockerfile syntax version annotation.