solution: wire first host caller and settle the method-policy open questions

[antoinetoussaint-byte]

Follow-up to #289 (merged in #294) and paired with #290.

#294 landed the host-enforceable solution_method_policy and the client-side dispatch gate (solution.EnforcingClientInterceptor, ceilings, WithCeiling, and the typed solution.Client). The enforcement is correct and fail-closed, but it is dormant: nothing in production constructs a Solution client or stamps a ceiling yet. Every open question below only becomes answerable once a real caller exists, so they are tracked together rather than split into independently-actionable issues.

Tasks

• Wire the first host caller. The CLI solution command group (the follow-up referenced in New agent kind: codefly:solution — registry entry, proto enum, manifest schema, proto service #287) should drive the lifecycle through solution.Client / WithCeiling. This is the linchpin that exercises everything below.
• Settle the two-API split. solution.Client (ceiling is a required, type-level argument) and the raw solutionv0.NewSolutionClient + exported WithCeiling both exist; the latter bypasses the former's guarantee. Decide the single canonical path and unexport/remove the other.
• Validate the ceiling vocabulary. Confirm CeilingInspect/Scaffold/Render/Publish map cleanly to real host operations (e.g. a deploy that packages and renders currently must use CeilingPublish), or recut the tiers.
• Confirm the Render network assumption. Render is annotated REGISTRY_READ because RenderRequest carries only artifact_reference (no bytes) and a solution executor's network is unmediated, so the executor pulls the artifact itself. If the host instead resolves the artifact host-side and hands the executor local content, Render should be OFFLINE and CeilingScaffold should re-admit it. This assumption is load-bearing and currently unverified against an implementation.
• Give the ceiling a real provenance. The ceiling is still whatever the caller passes. It becomes genuine enforcement (rather than a caller-chosen value) only when derived from an authorized operation/principal/environment at a trusted chokepoint — a design that needs the consumer to shape it.

Context

• Enforcement code: solution/policy.go, installed in agents/manager/loader.go.
• Acceptance bar (from New agent kind: codefly:solution — registry entry, proto enum, manifest schema, proto service #287): an end-to-end tracer bullet reaching an ArgoCD-synced namespace (obin-ai/lodestar#17).

🤖 Generated with Claude Code