Improve Disk Space Recovery for Partial Clones

Problem: Git's "partial clone" is a lifesaver for huge repos because it lets you download only the files you actually need. But once you download a file (a "blob"), it stays on your disk forever. Currently, Git has no way to "un-fetch" these files. Over time, your "partial" clone starts looking like a massive full clone, and the only fix is to delete everything and start over. Solution: I want to build a "reverse gear" for partial clones. My project will add a safe way for Git to drop large, local files you no longer need, while keeping a "promise" that it can get them back from the server later. I’ll be focusing on three main things: Safety: Ensuring Git double-checks that the server still has the file before we delete it locally. "Promise" Contract: Updating Git’s internal records so it knows a deleted file isn't missing, just stored remotely. User Control: Adding this to git maintenance so users can easily reclaim space without being C experts. By the end of the summer, Git will have a new capability to prune local blobs safely. This includes the core C logic for identifying and removing objects, integration with the git maintenance command, and a full suite of tests to ensure no data is ever lost.