Add ability to remove blobs

What does this MR do and why?

Adds the UI for removing blobs via repository settings.

⚠ this MR does not contain the backend integration. Changes are behind the rewrite_history_ui feature flag

MR breakdown

description	MR
Add ability to remove blobs	👈 this MR
Add ability to redact text	!154095 (merged)
Backend/frontend integration + docs	follow-up MR

MR acceptance checklist

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Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

Before	After

How to set up and validate locally

1. Enable the rewrite_history_ui feature flag.
2. Navigate to Project > Setting > Repository > Repository maintenance
3. Click on Remove blobs
4. The remove blobs drawer should open

Related to #450701