feat(sentry): enable on-error mobile session replay

[hawkrives]

Follow-up to #7464. Enables Sentry's mobile session replay on errors only, with aggressive masking.

What

Adds mobileReplayIntegration. When an error is captured, Sentry uploads a short video of the frames leading up to it — useful for reproducing UI-state-dependent bugs that don't surface from the stack trace alone.

Privacy / bandwidth posture

This is the reason this PR is separated out from #7497 and #7498.

• replaysSessionSampleRate: 0 — no blanket session recording. A replay is only produced if an error happens.
• replaysOnErrorSampleRate: 0.1 — 10% of error-containing sessions are recorded. Easy to tune up once we have a feel for volume and signal.
• maskAllText: true, maskAllImages: true, maskAllVectors: true — every text node, image, and SVG is blurred in the recording. These match the library defaults but are spelled out so the privacy choice is visible at the call site.

Verification before merging

Because replay ships screen recordings of real users, please don't merge without a manual pass on TestFlight:

• Trigger the debug "Send Exception" in Settings → Developer → Sentry event.
• Open the resulting replay in the Sentry UI.
• Confirm no text, image, or avatar renders through unmasked. In particular eyeball:
  • Directory / contact list cells
  • Dining menu items
  • Course catalog search results
  • Any screen showing a logged-in user's name or email

If anything leaks, we have two escape hatches:

• Per-element masking: wrap the view in <Sentry.Mask>.
• Per-screen opt-out: drop the screen class into excludedViewClasses on iOS.

Why stacked on the v8 branch

mobileReplayIntegration only exists in @sentry/react-native v8+, so this PR targets renovate/sentry-react-native-8.x. Will auto-retarget master once #7464 merges.

Test plan

• mise run tsc passes
• mise run lint passes
• mise run pretty:check passes
• mise run test passes (36 suites, 197 passing)
• Manual masking check on TestFlight (see above).