Labor Network product surface — the request-centric marketplace shell (follow-up to #109)

[mdheller]

Follow-up to #109 (labor-request contract landed). The contract now exists with teeth: request → response → evidence → fulfillment → trust, each receipted on the spine, trust bound to guild-scoped GKN standing. This issue tracks the product surface that satisfies it.

Per the SocioProphet Labor Network Charter v0.1 §9 (shell & interaction implications), the shell is organized around market operations, not feed consumption:

• Primary navigation: Requests · Matches · Work · Learn · Trust · Contracts · Governance.
• Primary composer: a request builder / availability-offer builder — not a generic status-update box (LN-007).
• Default home: relevant requests, active matches, work-in-progress, trust events — over generic posts.
• Messaging: contextual + permissioned; unlocks only on mutual interest / shortlist / award / dispute (LN-006).
• Capability passport: evidence, fulfillment history, references, availability, rate floor (LN-008); portable export (LN-019).
• Inspection model: center queue · filters left · evidence inspector right.

Must consume, not reinvent:

• the labor-request contract from feat(labor): request-centric labor contract — request→response→evidence→fulfillment→trust, each receipted (#108) #109 (contracts/labor/*) as the object model,
• the receipt spine (WO-B) for every write,
• GKN standing (guild-knowledge-network) for the trust/passport surface — no vanity score (LN-009),
• the Agora / work-knowledge plane as the persistence substrate.

Charter phased path: P1 request protocol + capability passport → P2 evidence/fit infra → P3 market coordination → P4 fairness/operating intelligence.

Refs #108, #109, GKN#9. @mdheller