Strip Timestripe mentions from docs

A case-insensitive grep for "timestripe" outside of assets finds these text occurrences:

• README.md:3 and CLAUDE.md:7: "built on the foundations of intuition.team and timestripe.com"
• src/routes/+page.svelte:17: the same sentence, shortened
• todos/update-readme-and-claude-md (lines 35 and 41) and todos/create-new-homepage (line 41): quotes of that sentence and a reference to "magazine/Timestripe content"
• todos/migrate-lighthouse-and-links-check:50: "(as in timestripe)" as a reference for a link checker setup
• reports/audit-meta-refactoring:197: YandexMetricsEventShareLink, the old Timestripe analytics component name

Whether the origin line stays in README is a judgement call; the point of this todo is to make it a deliberate one and remove the incidental mentions.

Tasks

• Decide on a single project description sentence and use it in README, CLAUDE.md and PROJECT_DESCRIPTION
• Rewrite the incidental mentions in the todo and report pages, or leave them if those pages are deleted as part of Remove Timestripe todos from site