Replace lodash usage

[techniq]

See just (copy/paste) or claude chat for some potential replacements.

• get
• set
• merge
• mergeWith
• isEqual
• isFunction
• camelCase

Should remove ~64K from bundles (see shadcn-svelte) and 621KB install size

[techniq]

FYI: tailwindcss-typography recently replaced merge with an inline implementation