Cache cateogires set operation results

[speed2CZ]

Description of the proposed changes

The global categories table for entity categories allow set operations using add, sub, mul metamethods

By default each operation returns a new object with the result, so that:
categories.LAND * categories.MOBILE ~= categories.LAND * categories.MOBILE

We can hook those meta methods and cache the results, significantly reducing object de/allocations.

Testing done on the proposed changes

1h long mission test resuls:

• total lookups: 915 724
• hits: 907 963
• misses: 7 761
  99.15% hitrate
  Average cache size ~195 entries

The test also indicated that the inner table of the cache should be pre-allocated with 4-hash size which will cover ~95% cases, significantly reducing the need of cache tables resizing.

Additional context

Ive checked if its worth caching on the UI and its probably not. UI Lua doesnt operate with categories nearly as much, with usually only few, if any, operations per tick. Also there were more misses than hits, nothing even comparable to the sim results.

Our code is already pre-computing the categories sets only once and storing them in local variables in a lot of places. This change improves the situation with the cases where it's not yet covered or where the sets are dynamic. (and also all the unoptimized mods)

Checklist

• Changes are annotated, including comments where useful
• Changes are documented in a changelog snippet according to the guidelines.
• Request 2-3 reviewers from the list of reviewers and their areas of knowledge.

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📥 Commits

Reviewing files that changed from the base of the PR and between b81d120 and 7569587.

📒 Files selected for processing (3)

• changelog/snippets/other.7280.md
• lua/simInit.lua
• lua/system/categories.lua

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