ci-image-improvements (#18)

Reviewed-on: #18
Co-authored-by: David Gwilliam <dhgwilliam@gmail.com>
Co-committed-by: David Gwilliam <dhgwilliam@gmail.com>

AGENTS.md

@@ -127,6 +127,29 @@ npm run db:setup-postgres
 DATABASE_PROVIDER=sqlite DATABASE_URL=file:./prisma/ci.db npm run test:acceptance
 ```
 
+### CI Runner Image
+
+**Note:** The CI runner image approach has been deprecated for Gitea Actions workflows.
+
+The original attempt to use a pre-built CI runner image with pre-installed dependencies encountered fundamental issues with how Gitea Actions handles workspace mounting. When Gitea Actions runs a container job, it mounts the workspace at a specific path (e.g., `/workspace/david/euchre_camp`), which hides the container's `/app` directory where dependencies were installed.
+
+**Current Approach:**
+- Workflows use standard `node:20-alpine` or `mcr.microsoft.com/playwright` containers
+- Dependencies are installed via `npm ci` in each workflow run
+- This is the recommended approach for Gitea Actions
+
+**Why the CI image approach doesn't work:**
+1. Dockerfile.ci installs dependencies in `/app`
+2. Gitea Actions mounts workspace at `/workspace/david/euchre_camp`
+3. Workspace mount hides the `/app` directory
+4. Symlinks from `/app/node_modules` don't work because `/app` is hidden
+
+**Alternative for performance:**
+If CI performance becomes an issue, consider:
+- Using GitHub Actions cache for node_modules
+- Using a self-hosted runner with persistent workspace
+- Using the main Dockerfile's `test-runner` target for release workflows (which works because it builds a complete image)
+
 ### CI/CD Pipeline
 The project uses Gitea Actions for continuous integration: