feat(deploy): PackagingModel + InstallGraphManifest compiler + Aspire publish step [SD-2]

[rickylabs]

Part of #830.

Generator-emitted typed PackagingModel (CLI-internal — deploy-core consumes the emitted manifest, never the model); pure compiler (PackagingModel, deploy.targets.<member>.package config) → InstallGraphManifest; the canonical deploy <target> build verb AND a named TS-AppHost pipeline.addStep(...) publish integration (installers via #825); schema move into deploy-core + ./install/./release publication (PM-20 stays pure extraction).

Depends on: #456, #829, PM-1 #512, PM-20 #531, #825.

• gate: emitted golden artifact via BOTH boundaries (publish step-graph run + direct verb)
• gate: scaffold.runtime; full jsr rubric on the deploy-core exports (the publishing slice)

Design source: PR #822 (rfc.md + plan.md rev 10, 9-cycle adversarial trail) in .llm/runs/rfc-single-deployment--orchestrator/. (plan.md §B.2/§B.4)