feat(mobile): Create PoolManagementStore with MobX

[rafamiziara]

Overview

Create MobX store for managing pool data, fetching pools from backend, and handling pool state.

Tasks

• Create stores/PoolManagementStore.ts with MobX observables
• Add observable state for pools list, loading states, errors
• Implement fetchPools() to call backend listPools
• Implement refreshPools() for manual refresh
• Add computed properties for filtered/sorted pools
• Integrate with existing RootStore pattern

Acceptance Criteria

• Store manages pools list reactively
• Fetches pools from backend successfully
• Handles loading and error states properly
• Integrates with existing MobX architecture

Related Documentation

• See docs/POOL_CREATION_ARCHITECTURE.md Component Architecture
• See docs/POOL_CREATION_TASKS.md Task 8

Labels: comp: frontend, type: feature

Milestone: Sprint 3: Pool Creation

Part of Epic: #35