feat(commands): add /verify command

Entry point for verification of existing replication projects.

.opencode/commands/verify.md

@@ -0,0 +1,41 @@
+---
+description: Verify replication results for a completed project
+agent: paper-director
+---
+
+Verify the replication results for an existing project.
+
+## Input
+
+Project directory: $ARGUMENTS
+
+If no directory specified, list available projects in workspace/ and ask user to select.
+
+## Workflow
+
+1. Validate project directory exists
+2. Check required files exist:
+   - `analysis/paper_structure.md`
+   - `analysis/replication_plan.md`
+   - `src/` with code
+   - `tests/` with tests
+3. Dispatch @test-runner to:
+   - Run test suite
+   - Compare results with paper
+   - Generate/update `reports/replication_report.md`
+4. Present verification summary
+
+## Example Usage
+
+```
+/verify workspace/attention_is_all_you_need/
+```
+
+Or without arguments:
+```
+/verify
+> Available projects:
+> 1. attention_is_all_you_need
+> 2. resnet
+> Please select a project to verify.
+```