refactor

- update `gix-fsck` crate status with all obvious features of `git-fsck`

Author: Byron

crate-status.md

@@ -776,16 +776,20 @@ See its [README.md](https://github.com/Byron/gitoxide/blob/main/gix-lock/README.
 * [x] [validate][tagname-validation] tag names
 
 ### gix-fsck
-* [x] validate connectivity when provided a specific commit as a starting point
-* [ ] validate connectivity of all `refs` in the index
-* [ ] identify objects that exist but are not reference by any reference nodes (e.g. `refs` or a provided commit)
-* [ ] add support for various options
-    * [ ] write dangling objects to the `.git/log-found` directory structure
-    * [ ] `strict` mode, to check for tree objects with `g+w` permissions
-    * [ ] consider reflog entries as reference nodes/heads
-    * [ ] when reporting reachable objects, include _how_ they are reachable
-        * [ ] which reference node(s) made them reachable
-        * [ ] parent commit(s)
+* [x] validate connectivity and find missing objects starting from…
+    - [x] commits
+    - [ ] tags
+    - [ ] tree-cache in the `index` or any entry within
+* [ ] validate object hashes during connectivity traversal
+* [ ] skipList to exclude objects which are known to be broken
+* [ ] validate blob hashes (connectivity check
+* [ ] identify objects that exist but are not reachable (i.e. what remains after a full graph traversal from all valid starting points)
+* [ ] write dangling objects to the `.git/log-found` directory structure
+* [ ] `strict` mode, to check for tree objects with `g+w` permissions
+* [ ] consider reflog entries from `ref` starting points
+* [ ] when reporting reachable objects, provide the path through which they are reachable, i.e. ref-log@{3} -> commit -> tree -> path-in-tree
+* [ ] limit search to ODB without alternates (default is equivalent to `git fsck --full` due to ODB implementation)
+* [ ] all individual [checks available in `git fsck`](https://git-scm.com/docs/git-fsck#_fsck_messages) (*too many to print here*)
 
 ### gix-ref
 * [ ] Prepare code for arrival of longer hashes like Sha256. It's part of the [V2 proposal][reftable-v2] but should work for loose refs as well.