fix(replay): Add missing rrweb type declarations

[Lms24]

This PR fixes a TypeScript error we encountered when using the 7.24.1 NPM package:

To generate type declarations, we use tsc (yarn build:types) which doesn't pull external type declarations into the resulting .d.ts files. We import types from rrweb which our internal types rely on. Because we now vendor rrweb, the rrweb-internal types are no longer getting installed in our users node_modules, producing typescript errors when they build their projects. To fix this, this PR vendors a "light" version of the two rrweb types we use.

[mydea]

LGTM! I'd maybe move the file to a different place, but no strong opinion on that. Great quick fix! IMHO we can later explore if we can make tsc somehow inline the types, but that's for a later point...!

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser - ES5 CDN Bundle (gzipped + minified)	19.68 KB (-0.01% 🔽)
@sentry/browser - ES5 CDN Bundle (minified)	60.94 KB (0%)
@sentry/browser - ES6 CDN Bundle (gzipped + minified)	18.46 KB (+0.01% 🔺)
@sentry/browser - ES6 CDN Bundle (minified)	54.49 KB (0%)
@sentry/browser - Webpack (gzipped + minified)	20.26 KB (0%)
@sentry/browser - Webpack (minified)	66.24 KB (0%)
@sentry/react - Webpack (gzipped + minified)	20.29 KB (0%)
@sentry/nextjs Client - Webpack (gzipped + minified)	47.08 KB (-0.13% 🔽)
@sentry/browser + @sentry/tracing - ES5 CDN Bundle (gzipped + minified)	26.5 KB (-0.12% 🔽)
@sentry/browser + @sentry/tracing - ES6 CDN Bundle (gzipped + minified)	24.92 KB (-0.14% 🔽)
@sentry/replay ES6 CDN Bundle (gzipped + minified)	41.79 KB (-0.01% 🔽)
@sentry/replay - Webpack (gzipped + minified)	37.91 KB (0%)