fix(docker): exclude logs and harness directories from container build

Updated .dockerignore to exclude:
- logs/ directory (contains large archived log files)
- harness/ directory (contains test reports and temporary files)

These directories contain large files that were causing container build
failures with 'archive/tar: write too long' errors. Excluding them reduces
the build context size and allows the container build to succeed.

The excluded directories are runtime-generated and not needed in the
production container image.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

.dockerignore

@@ -29,8 +29,10 @@ coverage.html
 ehthumbs.db
 Thumbs.db
 
-# Log files
+# Log files and directories
 *.log
+logs/
+harness/
 
 # Database files
 *.db