Streamline Docker setup and run tests via Docker

[tobiasmcnulty]

This PR makes several improvements to streamline the local Docker setup process:

1. Moves the Trac schema/table creation script out of the entry point and into a one-time initialization script, to avoid Postgres errors when it's inadvertently re-run when the web container is restarted.
2. Moves the management commands that create data out of the Docker entrypoint and into their own reset-local-db Makefile target.
3. Updates the Docker instructions with the applicable *.djangoproject.localhost:8000 links and ties back to the non-Docker setup.
4. Runs tests via Docker, to avoid reoccurrences of Docker only install instructions run into database connection error trac does not exist #2193 (or similar)

[Copilot]

Pull Request Overview

This PR streamlines the Docker development setup by improving the initialization process and adding comprehensive test execution via Docker. The changes simplify the dev entrypoint script, reorganize database initialization, and provide clearer documentation for Docker-based development workflows.

• Moved database initialization logic from the dev entrypoint to dedicated initialization scripts
• Added a new Makefile target for resetting local development data
• Enhanced GitHub Actions workflow to run tests via Docker Compose

Reviewed Changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
docker-entrypoint.dev.sh	Simplified by removing database initialization commands that are now handled elsewhere
docker-entrypoint-initdb.d/02_trac_schema.sh	New script to handle Trac database schema initialization during container startup
docker-compose.yml	Updated volume mounts to use the new initialization directory structure
README.rst	Enhanced Docker documentation with clearer step-by-step instructions and additional usage examples
Makefile	Added reset-local-db target to consolidate database reset commands
.github/workflows/docker-test-build.yml	Added Docker Compose setup and test execution for the tests.txt matrix
.dockerignore	New file to exclude unnecessary directories from Docker build context

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[tobiasmcnulty]

Hi, @easherma! Thanks again for your helping improving the Docker setup at the sprints. Would you be up for giving this a review when you have a moment? No rush.

[ulgens]

I think we can move the migrate command too.

[ulgens]

I added a small comment about the migrate command call, but other than it looks nice 🌻