build: publish browser CLI for DSH platforms

[254808127]

Summary

• add a static Linux x64 release asset
• add a signed and notarized macOS Intel release asset alongside the existing macOS ARM64 asset
• keep the existing Windows x64 asset and WorkBuddy platform selection unchanged
• bump the CLI release version and bootstrap pin to 1.1.12
• require all four assets in release CI and COS publication

Runtime scope

No Rust SDK, CLI command, API, CDP, authentication, or browser behavior code changes are included.

Validation

• cargo fmt --all -- --check
• cargo test --all-targets --locked: 9 passed
• cargo clippy --all-targets --locked -- -D warnings
• release workflow YAML and shell syntax checks
• browser-cli version reports 1.1.12

The four remote assets do not exist until this PR is merged and tag v1.1.12 is published.