docs(examples): add builder-adversary-lean — context hygiene + per-gate review

Isolates the two effects conflated in builder-adversary-stateless: keeps all the
CONTEXT HYGIENE (compact/diffs/lean loads) but ENFORCES full per-gate review
granularity (one claim per gate, one independent verdict per gate, no batching).
Tests whether the token saving is real efficiency vs reduced scrutiny.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

examples/builder-adversary-lean/agents.toml

@@ -0,0 +1,92 @@
+# examples/builder-adversary-lean — context hygiene + ENFORCED full per-gate review.
+#
+# Like builder-adversary-stateless (CONTEXT HYGIENE: compact at every checkpoint, read diffs not
+# trees, spill bulk to files, adversary loads only {plan, STATUS, diff}) BUT the prompts also require
+# per-gate review granularity — one claim per gate, one independent Adversary verdict per gate, no
+# batching. This isolates "leaner context" from "fewer review passes". Loop agents not resumed →
+# fresh session per phase. See README.md.
+#
+#   python3 ../../agents.py status --config agents.toml
+#   python3 ../../agents.py up     --config agents.toml      # needs `claude` on PATH
+
+[watchdog]
+signal_interval      = 30
+heavy_interval       = 300
+limit_probe_fallback = 300
+limit_reset_slack    = 45
+stall_grace          = 180
+
+[defaults]
+session_prefix = "blean-"        # REQUIRED — sessions: blean-builder, blean-adv, …
+log_dir        = ".ao-state"
+backend        = "claude"        # set to "demo" for a dependency-free mechanics-only run
+model          = "claude-sonnet-4-6"
+watch          = "heal"
+
+[backend.claude]
+bin             = "claude"
+flags           = "--dangerously-skip-permissions"
+remote_control  = true
+supports_resume = true
+prompt_delivery = "arg"
+process_name    = "claude"
+submit_key      = "Enter"
+stall_idle      = 300
+active_re = "esc to interrupt|Running tool|⠇|⠙|· \\d+"
+limit_re  = "spend limit|usage limit|limit reached|reached your .*limit|out of (credits|tokens)"
+fatal_re  = "redacted_thinking|blocks cannot be modified|cannot be modified"
+
+[backend.demo]
+bin             = "echo '[demo] {session} up (kickoff: {kickoff})'; exec sleep 1000000"
+prompt_delivery = "exec"
+
+[[agent]]
+name  = "builder"                # tmux session: blean-builder
+kind  = "loop"
+role  = "builder"
+dir   = "./work"
+watch = "heal+stall"
+
+[[agent]]
+name    = "adversary"
+session = "blean-adv"
+kind    = "loop"
+role    = "adversary"
+dir     = "./work-adv"
+watch   = "heal+stall"
+
+[[agent]]
+name    = "orchestrator"         # tmux session: blean-orchestrator
+kind    = "persistent"
+model   = "claude-opus-4-8"
+resume  = true
+watch   = "heal"
+prompt  = "You supervise this Builder/Adversary project. On startup: read machine-docs/ for the current phase's STATUS/REVIEW, confirm both loops + the watchdog are up, report the phase and any open findings/VETO. Then stay available; intervene only if the pair is stuck."
+
+[[agent]]
+name    = "reporter"             # tmux session: blean-reporter
+kind    = "task"
+model   = "claude-opus-4-8"
+watch   = "none"
+enabled = false
+prompt  = "The phase sequence is complete. Read machine-docs/ across all phases, write a short machine-docs/REPORT.md (what was built, each gate's final verdict, deferred items), then go idle."
+
+[[service]]
+name    = "cleanlogs"
+command = "python3 ../../agent-log.py follow-all"
+dir     = "."
+
+[loop]
+state_file       = "phase-idx"
+resume_phase     = true
+auto_advance     = true
+done_marker      = "## DONE"
+kickoff_template = "prompts/kickoff.md"
+roles_dir        = "prompts"
+handoff = { repo = "./work", claim_pings = "adversary", review_pings = "builder", inboxes = ["ADVERSARY-INBOX.md", "BUILDER-INBOX.md"], claim_pattern = "^claim", review_pattern = "^review", state_subdir = "machine-docs" }
+on_complete = { trigger_file = ".run-report-on-complete", run = "reporter" }
+
+phases = [
+  { id = "wc",   plan = "plans/wc.md",   status = "STATUS-wc.md" },
+  { id = "json", plan = "plans/json.md", status = "STATUS-json.md", models = { builder = "claude-opus-4-8" } },
+]