Clean up component exports

[ejmg]

Summary

Title says it all. With the notable exception of the ui/ directory (used by shadcn-ui), the overall structure has always been to define a non-default exported "public" component from an index.tsx that is located in a directory with camel casing. Ex: TransactionsTable is exported from components/TransactionsTable/index.tsx. This was simply the pattern chosen at the time and, overall, has worked just fine. It gives a top level directory that is easy to ID quickly for imports, prevents confusing/accidental default export aliasing, and gives the illusion of "private" component modules (anything not in index.tsx is not supposed to be used directly).

Update everything to fit this pattern again. Adding an eslint rule to enforce the model would be ideal, too.