new script: item-uses - show all workshop uses for selected item

[sizzlins]

Summary

Adds a new DFHack command item-uses that introspects the currently selected item and lists every workshop and task that can use it.

Usage

Select any item in-game (from inventory, stockpile, or trade screen), then run:
item-uses

Example Output

`
=== Uses for: steel bars ===
Type: BAR | Material: INORGANIC:STEEL

Metalsmith's forge:
- Forge metal items
- Forge weapons/armor/items
- forge angir body
- forge angir strings
...
Smelter:
- Melt metal item
Trade depot:
- Trade with merchants

Total: 142 uses across 6 workshops
`

Features

• Material flag inspection: IS_METAL, WOOD, LEATHER, IS_DYE, EDIBLE_COOKED, etc.
• Plant flag analysis: DRINK, MILL, DRY, THREAD with proper PLANT vs PLANT_GROWTH distinction
• Material reaction products: DRINK_MAT, DYE_MAT, CHEESE_MAT, SOAP_MAT, etc.
• Full reaction matching: Scans all game reactions and matches the primary reagent against the item
• Dynamic workshop resolution: Uses df.workshop_type/df.furnace_type enums for version-safe workshop names
• Smart filtering: Skips container/tool reagents and secondary inputs to avoid false positives
• Raw vs finished awareness: Raw materials show crafting uses; finished goods show 'Encrust with gem' and 'Melt metal item' instead

Technical Details

• Handles building fields stored as vectors (r.building.type[idx])
• Builds raw material type table safely to handle nil enum values across DF versions
• Only matches the first non-container reagent per reaction to avoid secondary ingredient false positives
• Growth-aware: EDIBLE_GROWTH only shown when the growth's own material has EDIBLE_COOKED

[sizzlins]