feat: ContentGuardianAgent, onboarding UX, Team Activity action wiring, docs, agent help modal

ContentGuardianAgent consolidation:
- Merge 3 duplicate classes into single source in specialized/content_guardian.py
- Watchdog audit_committee() with heuristic scoring, coverage gaps, overlaps, alerts
- Remove misleading rejection_rate() helper; use acceptance_rate directly
- Integrate audit + alerts + trend signals into today_workflow_service.py

Team Activity page:
- QualityAuditPanel: health ring, per-agent critiques, coverage gaps, overlaps
- TrendSignalsPanel: opportunity cards with urgency/impact/coverage bars
- AlertBanner: persistent dismiss via POST /alerts/{id}/mark-read
- AgentHelpModal: dialog showing all 8 agents with descriptions, tools, schedule
- QualityAuditPanel action buttons: Fill gap -> /content-planning, Resolve overlap, View CTA on alerts/issues
- TrendSignalsPanel action buttons: Create content from this trend -> /blog-writer with trend context state

Onboarding system:
- Step 4 validation: no auto-pass via basic_ready; requires persona data or explicit progression
- Step 5 validation: logs warning on auto-pass without integration data
- OnboardingCompletionService: single DB session, transactional task creation, upsert pattern
- Business-without-website: nullable website_url on SIFIndexingTask and MarketTrendsTask
- DeepCompetitorAnalysisExecutor: 5-min timeout, 10-competitor cap, asyncio.wait_for
- Persona generation: async with 30s timeout, falls back to scheduler
- OnboardingProgressService.reset_onboarding(): resets session + pauses all DB tasks
- OnboardingControlService.reset_onboarding(): also cancels APScheduler jobs
- FinalStep TaskSchedulingPanel: shows scheduled/failed tasks after completion, 8s auto-redirect
- onboarding_completed agent activity event logged to feed

Documentation:
- docs-site/features/onboarding/: overview, steps, scheduler-tasks, technical-reference (4 pages)
- docs-site/mkdocs.yml: added Onboarding System nav section
- docs-site/features/sif-agents/: overview, agent-directory, committee-system, content-guardian (4 pages)
- docs-site/features/team-activity/: overview, quality-audit, trend-signals, alert-system (4 pages)
- docs-site/features/todays-workflow/: updated overview, technical-architecture, workflow-guide, api-reference

backend/services/intelligence/agents/agent_orchestrator.py

@@ -230,7 +230,7 @@ class ALwrityAgentOrchestrator:
             # Content Guardian Agent
             if enabled_by_key.get("content_guardian", True):
                 try:
-                    from services.intelligence.sif_agents import ContentGuardianAgent
+                    from services.intelligence.agents.specialized.content_guardian import ContentGuardianAgent
                     from services.intelligence.txtai_service import TxtaiIntelligenceService
                     
                     # Initialize intelligence service if not already available
@@ -248,6 +248,19 @@ class ALwrityAgentOrchestrator:
                 except Exception as e:
                     logger.error(f"Failed to initialize ContentGuardianAgent: {e}")
 
+            # Content Gap Radar Agent
+            if enabled_by_key.get("content_gap_radar", True):
+                try:
+                    from services.intelligence.agents import ContentGapRadarAgent
+                    from services.intelligence.txtai_service import TxtaiIntelligenceService
+                    intel_service = TxtaiIntelligenceService(self.user_id)
+                    self.content_gap_radar_agent = ContentGapRadarAgent(intel_service, self.user_id)
+                    self.agents['content_gap_radar'] = self.content_gap_radar_agent
+                    initialized_agents.append("Content Gap Radar")
+                    logger.info(f"Initialized ContentGapRadarAgent for user {self.user_id}")
+                except Exception as e:
+                    logger.error(f"Failed to initialize ContentGapRadarAgent: {e}")
+
             logger.info(f"Created {len(self.agents)} specialized agents for user {self.user_id}")
 
             # Log initialization activity
@@ -449,7 +462,8 @@ class ALwrityAgentOrchestrator:
             "competitor": ["Competitor monitoring", "Threat analysis", "Response generation", "Strategy execution"],
             "seo": ["SEO auditing", "Issue prioritization", "Auto-fixing", "Strategy generation"],
             "social": ["Social monitoring", "Content adaptation", "Engagement optimization", "Distribution management"],
-            "trend": ["Trend detection", "Opportunity analysis", "Content angle generation"]
+            "trend": ["Trend detection", "Opportunity analysis", "Content angle generation"],
+            "content_gap_radar": ["Content gap detection", "SERP opportunity scoring", "Competitor content deep-dive", "ROI-based topic prioritization", "Content brief generation"]
         }
 
 # Service class for agent orchestration