feat: filterset modifiers

[roundaboutluke]

Adds visual modifiers to filtersets - glow, background, scale, rotation, badge, and label options that let users customize how filtered map objects appear.

Each filterset gets a "Visual" section in its editor with a live preview map.

Implementation:

• Three-layer MapLibre rendering (underlay → icon → badge) for clean visual separation
• Canvas-based overlay generation with caching for glow/background circles
• Filterset matching system that resolves which visual modifiers apply to each map object
• Live preview map in the modifier editor that mirrors the main map's layer structure
• Premade filtersets (hundos, PVP rank 1) ship with sensible defaults

Note: Also fixes an operator precedence bug in quest reward matching where item amount checks could match regardless of item id which was discovered while testing quest filter sets.

PS Built with AI assistance. Please review thoroughly as usual.

PPS My Portuguese Brother-in-Law says the PT translations are spot on, but the rest need vetting by native speakers. 😄

[roundaboutluke]

Closing and recreated on #103 due to drift