refactor: migrate useful legacy routes into API v1

[ralphhanna]

Summary

Migrates useful legacy operations into the canonical /api/v1 surface and routes each through BPMNAPI authorization.

Migrated

• GET /engine/get
• PUT /engine/restart
• Cursor-based /datastore/find
• Authorized instance deletion

Intentionally not migrated

• /query because it duplicates instance search
• /engine/status because it exposes global live-engine diagnostics
• /engine/upgrade because it is privileged administration rather than a runtime operation

Includes route inventory tests and a #5 changelog entry.

Stack

Depends on security/trusted-principal (#4).

Validation

• 18/18 focused web tests pass.

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Qualify restart queries before executing them

When the runtime principal is a non-admin or belongs to a tenant, this route still allows its query to select an item owned by another user or tenant. BPMNAPI's APIEngine.restart only extracts user.userName and passes the original query unchanged to Engine.restart, which calls dataStore.findItem(itemQuery) directly; unlike invoke and assign, it never calls user.qualifyItems. Therefore, exposing this route on the default /api/v1 surface lets any holder of the runtime API key restart an arbitrary completed instance if they know a matching item query. Qualify the query with the trusted principal before calling restart.

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