feat(aircoding): AirCoding V2 baseline — deterministic multi-agent architecture

Forked from OpenCode v1.17.4 with multi-agent system:
- 5 agents: aircoding, scheduler, worker, architect, reviewer
- Deterministic DAG scheduling engine (coordinator_tick)
- Tool whitelists as hard enforcement
- AirCoding validation plugin
- V1 requirements: C4 docs, ADR, AGENTS.md, debug-log.md
- Design documents in docs/

.opencode/command/rmslop.md

@@ -0,0 +1,15 @@
+---
+description: Remove AI code slop
+---
+
+Check the diff against dev, and remove all AI generated slop introduced in this branch.
+
+This includes:
+
+- Extra comments that a human wouldn't add or is inconsistent with the rest of the file
+- Extra defensive checks or try/catch blocks that are abnormal for that area of the codebase (especially if called by trusted / validated codepaths)
+- Casts to any to get around type issues
+- Any other style that is inconsistent with the file
+- Unnecessary emoji usage
+
+Report at the end with only a 1-3 sentence summary of what you changed