fix: replace Wright HTTP/1.x transport

[e54-bot]

Closes #288

Summary

• replace all Wright-owned ureq consumers with one HTTP/2-capable blocking HTTPS client configuration
• reuse clients within provider bootstrap/update and self-update workflows
• retain request timeouts, size limits, checksum verification, error handling, and activation behavior

Verification

• cargo fmt --all -- --check
• cargo clippy --workspace --all-targets --all-features -- -D warnings
• cargo test --workspace --all-targets --all-features
• clean production OPY provider bootstrap from releases.wrightkit.dev
• independent ablation: HTTP/1.1 transport fails against the production release policy while the HTTP/2 path succeeds

[Teakowa]

One blocking regression in the existing wright update validation/offline behavior.

[Teakowa]

LGTM