Implement Registry and Query Logic

[szabo137]

Description:

Implement a structured system to manage beams, experiments and facilities in LaserExperiments.jl.

• Experiments are combinations of beams (laser, electron, or more) and may be either generic or deployed.
• Facilities contain deployed experiments and provide location metadata.
• The runtime registry allows in-memory additions and queries, while contributions can be persisted to JSON and optionally submitted as GitHub pull requests.

Requirements:

• Runtime registry to hold lasers, electron beams, experiments, and facilities in memory.
• Functions to add entries to the runtime registry.
• Contribution functions to persist entries to JSON files (via database layer).
• Automatic update of facilities when adding experiments or deployed systems.
• Optional GitHub PR helper to contribute entries upstream.
• Validation to ensure references (laser, electron beam, facility) exist before saving.

Proposed API Examples:

# Add new laser beam
Registry.add_laser!(newlaser)

# Add new experiment at runtime
Registry.add_experiment!(newexp)

# Add new facility
Registry.add_facility!(newfacility)

# Query examples
Registry.experiments_in_facility("HiBEF")
Registry.facility_of_experiment("GammaRaySourceExp")
Registry.laser_of_experiment("InverseComptonExp")

# saving
Database.save() # saves registry in json files

Tasks:

• Implement runtime registry methods (add_experiment!, add_facility!, etc.).
• Implement contribution layer updating both experiments and facilities JSON files.
• Add validation functions to prevent dangling references.
• Implement unit tests covering runtime addition, persistence, and facility linkage.
• (Optional) GitHub PR helper for automatic submission.