Prove HTTP SSE and metadata view contracts #103

Parent

Spec: Complete the review-driven Effect API Query 0.1.0 programme

What to build

A bounded design proof fixes the public data, identity, service, and lifecycle contract for HTTP views.

Acceptance criteria

• Prove unambiguous SSE success projection and settle mixed-success limitations and decoded headers accompanying accumulated/live chunks.
• Separate SSE decoder controls from decoded request/custom-encoder input and identify controls that change view identity.
• Define acquisition versus consumption failures, HTTP metadata/Causes, empty-live errors, residual services, abort/finalization, and caller-owned resume policy.
• Define an opt-in decoded-data/status/plain-header metadata view with distinct identity and preserved declared WithHeaders behavior.
• Assess raw-byte representation/lifetime/retention separately and record a supported contract or evidence-backed limitation.
• Record the required HTTP/stream decision amendments and a complete input/output support matrix using installed public upstream APIs; perform no ungoverned installation.