update Big-M calculation on demand and energy tiers with large storage max sizes

[zolanaj]

Fixed

• Addresses a bug in which demand and energy charges are inaccurately calculated when large max storage system sizes are present.

[Copilot]

Pull request overview

This PR fixes a bug where demand and energy charges are incorrectly calculated when large storage system sizes are present. The fix updates the Big-M calculation logic to prevent artificially inflated values that occur when storage capacity significantly exceeds actual load requirements.

Key changes:

• Modified Big-M calculation to cap added storage power/energy at load-based Big-M values
• Added guard against array underflow in logging path handling
• Added test scenario with large storage sizes to validate the fix

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
test/scenarios/tiered_energy_demand.json	Adds test case with extremely large storage capacity (10^10 kW/kWh) to validate fix
src/logging.jl	Adds safety check for path splitting to prevent array underflow
src/constraints/electric_utility_constraints.jl	Updates Big-M calculations to cap storage contribution at load-based values

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[Copilot]

@zolanaj I've opened a new pull request, #548, to work on those changes. Once the pull request is ready, I'll request review from you.