Improve encounter presentation and battle map controls

[Daren9m]

Summary

• include full monster stat blocks when printing encounters
• expand encounter difficulty from three to five levels and make monster HP the primary difficulty signal
• normalize generated coin treasure to GP
• let DMs edit encounter name, description, and tactics
• make Battle Forecast a prominent callout
• add persistent map size, object-density, and terrain-variety controls to encounter and standalone map generation

Impact

Encounter preparation is easier to customize, printed encounters are table-ready, combat durability is more visible than rules XP, and DMs have meaningful control over generated battle maps.

Validation

• npm run lint
• 27 focused Vitest tests across encounter generation, 2024 rules, and map generation
• feature-scoped TypeScript check
• production build of the PR contents
• browser smoke test covering editing, printing, forecast visibility, and Dense/Wild 32×24 map generation with no console errors

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