docs(agents): allow N-level command paths in CLI contract

[axisrow]

Summary

• AGENTS.md described the canonical CLI shape as exactly direct <group> <command>, which is stale: PR refactor: recurse the command-tree walkers #674 made three command-tree walkers recursive specifically to support nested groups, and PR feat(masters): add direct masters adimages get #675-feat(masters): add direct masters adimages delete/set #677 shipped masters adimages get|add|delete|set as a real three-level leaf.
• The stale wording already produced a false P1 from a review bot on PR feat(masters): add direct masters adimages get #675, citing AGENTS.md L15-19 as evidence that the new nested group broke the contract (triaged and rejected there, but the underlying wording remained misleading for future reviewers).
• Reworded the contract to describe a path of one or more group segments plus a leaf command name, each segment validated by the same group/command rules (tests/test_cli_contract.py's GROUP_NAME_RE/COMMAND_NAME_RE only ever validated segment names, never tree depth), and added direct masters adimages get 123 as a documented example of the existing pattern.

Test plan

• pytest tests/test_cli_contract.py tests/test_smoke_matrix.py -q — 29 passed
• python -m direct_cli.cli masters adimages get --help — confirmed the example command's real signature (positional CAMPAIGN_ID, no --wizard-id flag)

Closes #680

🤖 Generated with Claude Code

[axisrow]

🔍 Local review (cycle 1) — round 3321ef62-f2da-48c0-b5ed-788198aad30a

Reviewed locally (/review + Codex companion), no bots pinged.

Verdict	Reviewer	Finding	Location
CLEAN	claude	No critical issues; docs wording matches the recursive _subcommands() walker and GROUP_NAME_RE/COMMAND_NAME_RE validation already in the codebase	AGENTS.md
CLEAN	codex	No critical blocker; docs-only change matches the already-shipped nested Click command, focused contract/registration checks passed	AGENTS.md

Totals: 0 FIX, 0 SKIP, 0 UNVERIFIED. Both reviewers approve.