# CLI Reachability Upload and Explain Commands

## Module
Cli

## Status
IMPLEMENTED

## Description
Commands for uploading call graphs (`stella reachability upload-callgraph`) and querying reachability status with explanation (`stella reachability list/explain`), with streaming upload and pagination support.

## Implementation Details
- **Command Group**: `src/Cli/StellaOps.Cli/Commands/ReachabilityCommandGroup.cs` -- reachability commands
- **ReachGraph Commands**: `src/Cli/StellaOps.Cli/Commands/ReachGraph/ReachGraphCommandGroup.cs` -- graph operations
- **ReachGraph Handlers**: `src/Cli/StellaOps.Cli/Commands/ReachGraph/ReachGraphCommandHandlers.cs` -- upload and query handlers
- **Commands**:
  - `stella reachability upload-callgraph <file>` -- upload call graph with streaming support. Options: `--digest <digest>`, `--format <format>`
  - `stella reachability list` -- list reachability results with pagination. Options: `--scan <id>`, `--status reachable|unreachable|unknown`, `--limit`, `--offset`
  - `stella reachability explain <cve>` -- explain reachability determination for a CVE with evidence chain

## E2E Test Plan
- [ ] Run `stella reachability upload-callgraph ./callgraph.json --digest sha256:abc123` and verify upload success
- [ ] Verify streaming upload for large call graphs
- [ ] Run `stella reachability list --scan <id>` and verify reachability results displayed
- [ ] Run `stella reachability list --status reachable` and verify filtering
- [ ] Run `stella reachability explain CVE-2024-1234` and verify explanation with evidence chain
- [ ] Verify pagination with `--limit` and `--offset`
- [ ] Verify `--format json` output for automation