feat(core): Write data from setUser, setTags, setExtras, setTag, setExtra, and setContext to isolation scope

[lforst]

In the new scope model, all the global Sentry.setX() APIs should write to the isolation scope. This PR introduces that in the hub as a compatibility and migration layer until we deprecate the hub in v8.

One exception to this rule is the addBreadcrumb function, which I opted not to let write to the isolation scope to avoid duplicate breadcrumbs. We can still write breadcrumbs to the isolation scope ourselves by calling .addBreadcrumb() on the isolation scope directly. This should therefore be non-blocking to anybody.

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser (incl. Tracing, Replay, Feedback) - Webpack (gzipped)	77.11 KB (+0.12% 🔺)
@sentry/browser (incl. Tracing, Replay) - Webpack (gzipped)	68.47 KB (+0.13% 🔺)
@sentry/browser (incl. Tracing, Replay) - Webpack with treeshaking flags (gzipped)	62.13 KB (+0.15% 🔺)
@sentry/browser (incl. Tracing) - Webpack (gzipped)	32.5 KB (+0.29% 🔺)
@sentry/browser (incl. Feedback) - Webpack (gzipped)	31.09 KB (+0.28% 🔺)
@sentry/browser - Webpack (gzipped)	22.44 KB (+0.43% 🔺)
@sentry/browser (incl. Tracing, Replay, Feedback) - ES6 CDN Bundle (gzipped)	74.79 KB (+0.13% 🔺)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (gzipped)	66.44 KB (+0.13% 🔺)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (gzipped)	32.27 KB (+0.28% 🔺)
@sentry/browser - ES6 CDN Bundle (gzipped)	24.09 KB (+0.47% 🔺)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (minified & uncompressed)	209.43 KB (+0.2% 🔺)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (minified & uncompressed)	97.49 KB (+0.42% 🔺)
@sentry/browser - ES6 CDN Bundle (minified & uncompressed)	72.08 KB (+0.57% 🔺)
@sentry/browser (incl. Tracing) - ES5 CDN Bundle (gzipped)	35.29 KB (+0.28% 🔺)
@sentry/react (incl. Tracing, Replay) - Webpack (gzipped)	68.85 KB (+0.13% 🔺)
@sentry/react - Webpack (gzipped)	22.48 KB (+0.43% 🔺)
@sentry/nextjs Client (incl. Tracing, Replay) - Webpack (gzipped)	85.54 KB (+0.13% 🔺)
@sentry/nextjs Client - Webpack (gzipped)	49.65 KB (+0.23% 🔺)
@sentry-internal/feedback - Webpack (gzipped)	17.11 KB (+0.64% 🔺)