[Documentation] Publish the v0.2 mission, vision, architecture, safety, and migration contract

[pate0304]

Outcome

Make Project Capability Compiler v1 understandable to contributors and users without relying on catalog-size marketing.

Acceptance criteria

• PROJECT_GOAL and ROADMAP contain the mission, vision, master goal, phases, success metrics, and governance.
• README explains outcome-first dynamic project team generation in short language.
• Architecture documents Team IR, evidence flow, policy admission, topology, capability probes, and lifecycle.
• Threat model and privacy policy cover assisted synthesis, evidence egress, ownership, freshness, and prompt injection.
• Usage and validation docs include exact commands, limitations, and evidence levels.
• v0.1 compatibility and migration behavior are explicit.