docs: update readme

feat: default invoice number when no invoices present

fix: when local storage is empty

Merge pull request #4 from dev-geddy/feat/prefill-customer-modal

feat: pre-fill customer info modal

feat: fallback blank config values

refactor: cleanup legacy code leftovers

fix: empty local storage crashes production app

Merge pull request #1 from dev-geddy/feat/expandable-provider-custome…

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feat: toggle customer/provider forms visibility

chore: update package info

refactor: remove unused edit mode config