Add traverse-starter validate and summarize WASM agents (spec 058)

[enricopiovesan]

Governing Spec

• 058-workflow-pipeline-execution
• 017-ai-agent-packaging
• 009-expedition-example-artifacts

Project Item

Project 1 item for issue #554 (Status: In Progress, claimed with agent:claude).

Summary

Adds the two WASM agents for the traverse-starter multi-capability pipeline showcase (spec 058, reference-apps #110):

Capability	Input	Output
traverse-starter.validate	{ note }	{ valid, issues[] }
traverse-starter.summarize	process output fields	{ summary, wordCount }

• Contracts at contracts/examples/traverse-starter/capabilities/{validate,summarize}/contract.json, mirroring the existing process contract (wasm, wasi-command, no host/network/filesystem access, manual-approval policy).
• Agent packages examples/traverse-starter/{validate,summarize}-agent/ with manifest, stub Rust source, fixture build script, and .wasm artifact (fnv1a64:dffc31d6401c84d6 digest, same fixture bytes as the process agent).
• Runtime request examples examples/traverse-starter/runtime-requests/{validate,summarize}.json.
• Deterministic native implementations wired into both example executors (ExpeditionExampleExecutor used by serve, AgentPackageExampleExecutor used by execute-agent): no network, no model, no randomness.
  • validate: empty/whitespace note → valid: false with non-empty issues; note over 2000 chars flagged; valid note → valid: true, issues: [].
  • summarize: deterministic one-line summary from process output fields plus its whitespace word count.
• execute-agent output rendering extended for both capabilities (extracted push_capability_output_lines helper to stay within the function-length lint).

Validation

• cargo test — all 25 suites pass; 8 traverse-starter tests including determinism tests for both agents (same input run twice → identical output), empty-note rejection, max-length flagging, process→summarize composition, and execute-agent runs for both runtime requests.
• cargo clippy --all-targets -- -D warnings — clean.
• cargo fmt — applied.
• bash scripts/ci/spec_alignment_check.sh — passes (no governed spec files changed).

Downstream unblocked

• Multi-capability workflow orchestration: pipeline execute surface for reference apps #558 pipeline wiring (traverse-starter.pipeline steps 1 and 3)
• reference-apps Standardize local Traverse runtime home for generated binaries and adapter config #110

Closes #554.

🤖 Generated with Claude Code