fix(query_router): rename query_runner to query_router and fix service configuration

[jdhoffa]

This PR addresses issues with the query service configuration and naming inconsistency.

Changes:

• Renamed service from query_runner to query_router across the codebase for consistency
• Added explicit port configuration for the query router service (8002)
• Fixed environment variable handling in Docker Compose setup
• Updated service healthcheck configurations to use appropriate hostnames and variables
• Added QUERY_ROUTER_PORT to .env.example
• Added proper dependencies between services with healthchecks
• Added tower dependency to the service's Cargo.toml
• Updated documentation in README with accurate examples and usage instructions
• Removed unnecessary environment variable settings from Dockerfiles

Testing:

All services now start correctly using docker compose up with proper dependency resolution and port configurations.

[Copilot]

Pull Request Overview

This PR renames the query service from query_runner to query_router and updates its service configuration, environment variables, and documentation. Key changes include:

• Deleting the old query_runner code and introducing new query_router service code.
• Updating Docker Compose, Cargo.toml, and CI workflow files to reflect the new naming and configuration.
• Enhancing error handling and healthchecks in the new query_router service.

Reviewed Changes

Copilot reviewed 7 out of 11 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
query_runner/src/main.rs	Removed the old query_runner service implementation.
query_router/src/main.rs	Added new query_router service code with improved endpoints.
query_router/Cargo.toml	Updated package name and dependency versions.
docker-compose.yml	Adjusted service definitions and healthchecks for query_router.
README.md	Updated instructions and examples to reference query_router.
.github/workflows/ci.yml	Modified working directories and service names for CI.
.github/workflows/build.yml	Updated build context and tags to reference query_router.

Files not reviewed (4)

• .env.example: Language not supported
• api/Dockerfile: Language not supported
• llm_engine/Dockerfile: Language not supported
• query_router/Dockerfile: Language not supported

Comments suppressed due to low confidence (1)

query_router/src/main.rs:150

• The error message instructs to set the 'PORT' environment variable, but the service uses 'QUERY_ROUTER_PORT'. Please update the error message to reference 'QUERY_ROUTER_PORT' for consistency.

tracing::error!("Port {} is already in use. Try setting a different port with the PORT environment variable.", port);