feat: Goal Tags and Fixed Custom Goals

[cjs8487]

Adds a fixed goal placement option for custom board layouts and goal tags, a new, opaque, generation mechanic that applies only for the goal selection process (and are not exposed anywhere else).

New Features

Goal Tags

Goal tags are a new, opaque generator option only used during the goal selection phase of the generator. They function similarly to categories in that sense; generation options for the main game mode and variants can modify the goal list based on them. The goal list can also be searched/filtered on tags, but they are not displayed with categories when displaying detailed goal information on boards.

Generator Options

Filters

• Goal Tag Inclusion Filter
  • Only includes goals with at least one of the specified goal tags. Goals with no tags are never included
• Goal Tag Exclusion Filter
  • Excludes any goals with one or more of the specified filters. Goals with no tags are always included

Custom Board Layout

• New "Fixed" goal option, which allows for selection a specific goal to always be placed in that cell. Fixed goals are never considered eligible to be placed in any other cell, even if there are multiple options for a fixed cell.