Fix monitoring runs not starting due to missing terms

[scottfrasso]

Summary

• Monitoring runs silently skipped when no terms were configured because create_project() seeded default providers but not a default monitoring term
• Auto-seeds a default term from brand name on project creation so the first "Run Now" click works
• Returns a detailed 400 error when triggering monitoring without terms, explaining exactly how to fix it
• Creates a critical configuration_error alert when scheduled runs skip due to missing config
• Adds client-side validation in the setup wizard requiring at least one monitoring term

Test plan

• All 215 existing tests pass
• New test: test_trigger_monitor_no_terms_returns_400 verifies 400 response
• Extended test_no_terms_skips_run verifies alert creation
• Manual QA: setup wizard blocks submission without terms
• Manual QA: project creation auto-seeds term from brand name
• Manual QA: "Monitor Now" on termless project shows toast with instructions
• Manual QA: scheduled run skip creates visible alert in AlertsFeed
• ruff, tsc --noEmit pass clean

🤖 Generated with Claude Code

[scottfrasso]

Code review

No issues found. Checked for bugs and CLAUDE.md compliance.

🤖 Generated with Claude Code

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