Add /adjudicate command: debate low-priority backlog to a verdict

Parked P2/P3 technical items accumulate faster than I can judge their
necessity. /adjudicate runs a grounded per-item debate (investigator →
build/drop advocates → judge) over a repo's ROADMAP and routes each to
DROP / DO / ESCALATE, so I ratify decisions instead of researching them.

Recommend-only in v1; verdict autonomy is gated by blast radius, not
priority. ROADMAP-only input — nudges /triage rather than reading the
raw inbox.

adapters/claude/commands/adjudicate.md

@@ -0,0 +1,20 @@
+---
+description: Debate each low-priority (P2/P3) backlog item on this repo's ROADMAP to a DROP/DO/ESCALATE verdict — recommend-only, applied on your approval
+argument-hint: [optional scope, e.g. a ROADMAP item number or "P3"]
+---
+
+Adjudicate the low-priority technical backlog of the repository in the current working
+directory. Scope, if any: $ARGUMENTS
+
+Your complete orchestration guide — phases, the per-item investigate→debate→judge pipeline,
+the three verdicts (DROP / DO / ESCALATE), and the report + approval flow — is at:
+
+    ~/Projects/standards/guides/adjudicate.md
+
+Read it in full first, then follow it exactly. If you cannot read that file, stop and report
+precisely that — do not improvise the adjudication.
+
+Claude Code specifics for Phase 2: per item, launch the investigator first, then the build- and
+drop-advocates as a single parallel batch, then the judge; run items concurrently in batches to
+keep the fan-out manageable. These are read-only role agents — the only write is the ROADMAP
+edit in Phase 4, after the owner approves.