feat(FN-2997): merge fusion/fn-2997-2

Merges the FN-2997 research CLI feature (275-line `research` command with routing, error handling, and docs), a droid CLI provider card for onboarding, a consolidated mock helpers module shared across CLI/dashboard/engine, the SSE architecture reference documentation, and the droid CLI probe module

Fusion-Task-Id: FN-2997

packages/cli/skill/fusion/references/cli-commands.md

@@ -40,6 +40,20 @@ fn task logs FN-001 --limit 50            # Limit log lines
 fn task logs FN-001 --type tool           # Filter by log type
 ```
 
+## Research
+
+```bash
+fn research create --query "question"          # Create research run
+fn research create --query "question" --wait   # Wait for completion
+fn research list                                 # List runs
+fn research ls --status failed --limit 20        # Filter by status
+fn research show RR-001                          # Show one run
+fn research export RR-001 --format json          # Export to JSON
+fn research export RR-001 --output ./run.md      # Export to specific path
+fn research cancel RR-001                        # Cancel active run
+fn research retry RR-001                         # Retry failed/cancelled run
+```
+
 ## Mission Management
 
 ```bash