docs: update documentation links and expand Q2-Q3 2026 milestone plan

- Fix broken documentation links in intro.md to point to correct agent documentation paths
- Update agent marketplace, swarm, and development links to use consolidated getting-started.md
- Expand Q2-Q3 2026 milestone plan from "OpenClaw Agent Economic Model & Scalability" to "Global Marketplace Expansion"
- Add comprehensive global infrastructure scaling strategy with multi-region deployment
- Include cross-chain agent economics

docs/11_agents/collaborative-agents.md

@@ -496,7 +496,7 @@ aitbc agent consensus configure research_team \
 
 - [Advanced AI Agents](advanced-ai-agents.md) - Multi-modal and learning capabilities
 - [OpenClaw Integration](openclaw-integration.md) - Edge deployment options
-- [Swarm Intelligence](swarm/overview.md) - Collective optimization
+- [Swarm Intelligence](swarm.md) - Collective optimization
 
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