build(deps): drop OpenSSL, move TLS stack to rustls

Some users installing the runner on macOS hit errors about OpenSSL not
being installed, because our HTTP stack pulled in native-tls (which links
OpenSSL on Linux and complicates static/musl and source builds).

Move the whole TLS stack to rustls, removing openssl-sys and native-tls
from the dependency tree entirely:

- reqwest 0.12 -> 0.13 with explicit rustls (drop native-tls-vendored)
- reqwest-middleware 0.4 -> 0.5, reqwest-retry 0.7 -> 0.9 (needed for 0.13)
- gql_client fork bumped to reqwest 0.13 + rustls, repointed git rev

reqwest 0.13 also defaults to rustls, matching what Astral's uv does.

Fixes COD-2857
Co-Authored-By: Claude <noreply@anthropic.com>

Author: art049