Implement warpctrl readonly metadata shard

[zachlloyd]

Summary

• Adds metadata-only local-control protocol/catalog support for app active/inspect, action list/get, and window/tab/pane/session list actions.
• Wires app-side metadata handlers, target validation, permission checks, and CLI subcommands for the structural read-only shard.
• Adds focused protocol, CLI, and app local-control tests covering action metadata, permissions, selectors, and parser behavior.

Validation

• cargo fmt --manifest-path /tmp/warpctrl-readonly-metadata/warp/Cargo.toml --all
• git -C /tmp/warpctrl-readonly-metadata/warp diff --check
• cargo check --manifest-path /tmp/warpctrl-readonly-metadata/warp/Cargo.toml -p local_control -p warp_cli
• cargo check --manifest-path /tmp/warpctrl-readonly-metadata/warp/Cargo.toml -p warp --features warp_control_cli
• cargo nextest run --manifest-path /tmp/warpctrl-readonly-metadata/warp/Cargo.toml -p local_control --no-fail-fast
• cargo nextest run --manifest-path /tmp/warpctrl-readonly-metadata/warp/Cargo.toml -p warp_cli --no-fail-fast local_control
• CARGO_BUILD_JOBS=1 cargo nextest run --manifest-path /tmp/warpctrl-readonly-metadata/warp/Cargo.toml -p warp --features warp_control_cli --no-fail-fast local_control

Co-Authored-By: Oz oz-agent@warp.dev

Conversation: https://staging.warp.dev/conversation/05fefcfe-b511-4529-93a3-f9eaf9f001f5
Run: https://oz.staging.warp.dev/runs/019e566e-96c6-7a85-a60b-41ee6f027572
This PR was generated with Oz.