Adds ten research levels for the Krastorio 2 flare stack. Each level adds
100% of the original base crafting speed: level 1 is 2× and level 10 is 11×.
Existing and newly placed flare stacks are synchronized with the researched
level. Quality and mirroring are preserved when replacing a flare stack.

Requires Factorio 2.1.23+, Krastorio 2.1.4+, and Space Exploration 0.7.63+.
Version 1.0.1 recognizes science packs as item prototypes in Factorio 2.1,
preserving the intended science ingredients in the research costs.
Recovery command: /flare-stack-upgrades-sync
License: MIT (included in the archive).

Working flare stack behavior has been confirmed by the user in Factorio 2.1.23.