style(ui): shorten PNG export helper text for clarity

feat(docs,accessibility): add filtering & performance section, update export formats (PNG/SVG), and fix contrast + a11y issues

Merge pull request #13 from coder-ralph/refactor/api-remove-filter-payload

refactor(api): remove unused filter payload from tree route

Merge pull request #12 from coder-ralph/feat/large-repo-filters

fix(tree): use strict null check for maxDepth

fix(ui): correct filter summary when only one filter is active

fix(tree): correctly exclude files matching patterns

feat: improve large repo handling with filters, validation UX, export safeguards, and provider fix

fix(accessibility): correct help dialog trigger ARIA semantics

feat(header): simplify help actions and update help modal content

feat(landing): improve export feature copy to include PNG/SVG and sharing

docs(readme): update launch badges layout and size

docs(readme): add Product Hunt and Open-Launch badges

feat(generator): add folder and file counts