Add Attentive and ClickMagick as data sources

[mkzsg]

Summary

• Adds Attentive (SMS marketing) as a new source + organization
• Adds ClickMagick (link tracking / attribution) as a new source + organization

Test plan

• Source IDs match filenames (attentive, clickmagick)
• Each source references a valid organization defined in this PR
• Categories used (MARKETING, ANALYTICS, ADVERTISING) all exist in categories.json
• dataVisibility set to PRIVATE (per-account data)

🤖 Generated with Claude Code

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[mendozamedina]

LGTM