feat(iit): Initialize IIT Manager Agent MVP - Day 1 complete

- Add iit_schema with 5 tables
- Create module structure and types (223 lines)
- WeChat integration verified (Access Token success)
- Update system docs to v2.4
- Add REDCap source folders to .gitignore
- Day 1/14 complete (11/11 tasks)

git-fix-lock.ps1

@@ -0,0 +1,20 @@
+# Fix Git lock file issue
+# Remove stale lock file and retry commit
+
+cd D:\MyCursor\AIclinicalresearch
+
+Write-Host "Checking for Git lock file..." -ForegroundColor Yellow
+
+$lockFile = ".git/index.lock"
+
+if (Test-Path $lockFile) {
+    Write-Host "Found stale lock file. Removing..." -ForegroundColor Yellow
+    Remove-Item $lockFile -Force
+    Write-Host "Lock file removed successfully!" -ForegroundColor Green
+} else {
+    Write-Host "No lock file found." -ForegroundColor Green
+}
+
+Write-Host ""
+Write-Host "Now you can run git commands again." -ForegroundColor Cyan
+