fix(agentic): root Antigravity runs at the requested cwd

[rickylabs]

Summary

agy --print roots its workspace at ~/.gemini/antigravity-cli/scratch unless a project is
supplied. The adapter passed cwd and agy's init event echoed it back, so the mismatch was
silent — the agent simply read somewhere else. The headless probe only echoes a marker, so it
passed anyway.

Found while smoke-testing Antigravity ahead of an unattended run train.

Changes

• --new-project when no --project is supplied, rooting the workspace at cwd
• an opt-in unattended request flag trading --sandbox for --dangerously-skip-permissions;
  the default is unchanged
• structured_output derived from the probe instead of pinned to unsupported (CLI 1.1.8 added
  --output-format json|stream-json)

Evidence

Direct, on CLI 1.1.9:

• without --new-project, reading a file that exists in cwd:
  "The file a.txt does not exist in the current directory (/home/codex/.gemini/antigravity-cli/scratch)"
• with --new-project: returns alpha, the actual contents
• subagent swarm with --new-project: A=alpha B=bravo, two parallel subagents, fixture intact

Under --dangerously-skip-permissions without the fix, subagents created the files they could
not find, with invented contents, and reported success — the original alpha/bravo fixture was
overwritten with foo/bar.

Through the tool, live headless probe:

	before	after
status	passed	passed
failureSignals	["timeout"]	[]
structured_output	unsupported (pinned)	unknown (no structured probe yet)

deno test .llm/tools/agentic/runtime/ — 154 passed, 0 failed.

Acceptance evidence

• An Antigravity run driven through the adapter operates in the requested cwd and can read files there. — verified before/after; --new-project returns real file contents where the unfixed invocation reports the scratch path
• Unattended runs can opt out of the sandbox explicitly, and the default stays sandboxed. — unattended flag; --sandbox remains the default branch
• structured_output reflects what the installed CLI does rather than a pinned constant. — derived from observation.structuredOutputParsed, with a test for supported and unsupported
• The live headless probe reports no failure signals. — failureSignals: [], down from ["timeout"]

Closes #1062

🤖 Generated with Claude Code

https://claude.ai/code/session_01RLqimdJHXcojxbUGBPVfci