Pass run_agents metadata through child launch and confirmation

[warp-agent-staging]

Description

Pass run_agents batch metadata and child overrides to child-run creation. This lets orchestrators label each child while retaining existing server-owned explicit > inherited > automatic precedence.

Review guide

Start with protocol conversion, RunAgentsExecutor dispatch, and remote request preparation. GUI and TUI confirmation reconstruction must preserve both maps. TUI coverage dispatches the normal Accept action and checks the controller’s captured request. Most other edits initialize empty maps at existing constructors. The action variant boxes its request so added metadata does not enlarge every action. MacOS Clippy diagnosed a 320-byte request versus the next-largest 112-byte variant; scoped Linux Clippy alone did not catch that target-dependent layout gate.

Metadata persistence also travels through local child creation for consistency; embedded-local and standalone-local environment injection remain out of scope. Hosted/self-hosted metadata comes from the server's environment transport before setup, not from new prompt injection. The runtime rejects raw managed-secret names that collide with injected metadata, including empty values.

Depends on protocol PR #398, pinned at 6b33333f17ae74f1d18769672d6594d095b3f3da. Pair with worker PR #167 and server PR #19546. Deploy this runtime and worker conflict protection before metadata-producing server rollout. Older clients continue to create children with inherited metadata only.

The protocol pin also includes existing upstream web-fetch usage fields. Two unrelated exhaustive test constructors gain defaults solely to compile against that additive protocol version. The lockfile changes only the protocol source revision.

Approved collision-check limits: custom-image baked-in ENV and Kubernetes EnvFrom names are not inspected; operators must avoid WARP_METADATA_ there.

Linked Issue

REMOTE-3439.

• The linked issue is labeled ready-to-spec or ready-to-implement. This work uses an approved Linear contract, not a GitHub issue with those labels.
• Where appropriate, screenshots or a short video of the implementation are included below (especially for user-visible or UI changes). No rendering change; validation is code and shell tests.

Testing

Passed 266 tests on the current candidate, covering metadata conversion, independent child overrides, empty-value preservation, remote wire payload, secret protection, and GUI/TUI orchestration confirmation and dispatch.

Command: cargo nextest run --locked -p ai -p warp -p warp_tui -E 'test(metadata) | test(secret_env_vars) | test(run_agents) | test(orchestration_config) | test(orchestration_block) | test(prepared_remote_request_matches_gui_wire_semantics)' --no-fail-fast.

Also passed cargo clippy --locked -p ai -p warp -p warp_tui -p warp_graphql --all-targets --tests -- -D warnings, followed by ./script/format. Both commands used CARGO_HOME=/home/agent/.cargo CARGO_TARGET_DIR=/tmp/warp-metadata-target.

The MacOS enum-size diagnostic is addressed by boxing the action payload, without suppressing the lint. Normal push triggered eligible cross-platform CI on the new head. Those results are pending, not green; green required checks remain a merge gate.

An intermediate Clippy attempt exhausted disk; deleting only temporary Cargo incremental caches recovered capacity and the retry passed. No live hosted service launch or local Mac/Windows runner was exercised.

• I have manually tested my changes locally with ./script/run. No rendering change or computer-use verification scope.

Agent Mode

• Warp Agent Mode - This PR was created via Warp's AI Agent Mode

CHANGELOG-OZ: Orchestrators can attach batch and per-child run metadata for grouping and setup workflows.

Plans:

• Child-run metadata propagation and hosted setup environment
• Fix run_agents action enum size CI failure

[warp-agent-staging]

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