feat: add agent-native session control

[almogdepaz]

summary

• add wolfpack session create <project> for server-owned top-level sessions
• add wolfpack agent spawn <project> for same-harness children; retain wolfpack session open as a deprecated compatibility alias
• pass launch prompts atomically as opaque argv values with no terminal-readiness race or shell interpolation
• expose stable broker sessionId values across create/spawn/list/status/read/send/wait/kill
• resolve human names or opaque IDs against structured identity and fail closed on ambiguity
• provide lightweight JSON list/status paths without terminal preview scraping
• persist structured parent identity and notify the active desktop parent so the browser can open the child in its existing grid ownership flow
• preserve ordinary global/tailnet auth policy and side-effect-free help paths
• reject deploy-local.sh --broker=yes before mutation when invoked from a broker-owned Wolfpack session
• replace the kernel-socket-timing CI test with deterministic backpressure coverage of the real broker forwarder

command contract

wolfpack session create <project> [--harness <agent>] [--prompt <instruction>] [--json]
wolfpack agent spawn <project> [--prompt <instruction>] [--json]
wolfpack list --json
wolfpack session status|read|send|wait <session-or-id> ...
wolfpack kill <session-or-id> [--json]

verification

• Bun: 1,785 passed
• Rust: 174 passed
• Playwright: 86 passed, 109 intentional project skips
• strict TypeScript passed
• dependency audit: 0 vulnerabilities
• schema/assets deterministic
• four-target compiled build and CLI help passed
• shell syntax and shellcheck passed
• git diff --check passed
• fresh GitHub Actions test job passed

deployed QA

• top-level create, child spawn, deprecated alias, stable-ID list/status/read/send/wait/kill, --no-enter, coded JSON failures, and ambiguous-selector rejection passed
• atomic top-level and child prompts matched through real PTYs
• structured parent identity and desktop child auto-grid passed in the deployed browser
• disposable QA sessions were removed

project-prefix selection remains tracked separately in #178. alternate-screen snapshot isolation is independent in #184.