Cypher as the agent-facing query language: implementation

What

Ship the read-only openCypher subset as the query language agents use against Orbit, replacing the DSL as the primary entry point in the CLI, MCP tools, and docs. #1258 recorded the decision; this issue tracks delivery to production.

Why

Agents already know Cypher. The DSL costs every agent a learning loop and every failed query a network round trip.

Covers

• decision: #1258
• test migration: #1306
• threat model for the Cypher front end runs in parallel (GA doc, Security row 4)

Source

Orbit GA Planning, section "Orbit AX (Agent Experience)", row 1.