feat(rsocials): graph-based campaign creation with brief-to-canvas pipeline
Add campaign planner as primary creation tool. Brief inputs in collapsible
sidebar generate editable node graph via Gemini 2.5 Flash. New input node
types (goal, message, tone) with feeds edges to downstream post/thread nodes.
Stale tracking propagates when inputs change; batch regen + single-node AI fill.
- schemas: goal/message/tone node types, feeds edge, stale tracking, schema v8
- mod: 3 API endpoints (from-brief, regen-nodes, ai-fill-node) + /campaign-flow page
- planner: ports, wiring, rendering, inline config, brief sidebar, context menu
- css: brief panel, platform chips, stale badges, feeds edge styles
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>