docs: n34 book

Signed-off-by: Awiteb <a@4rs.nl>

docs/patch/fetch.md

@@ -0,0 +1,21 @@
+# Fetch a Patch By ID
+
+> `n34 patch fetch` command
+
+**Usage:**
+```
+Fetches a patch by its id
+
+Usage: n34 patch fetch [OPTIONS] <PATCH_ID>
+
+Arguments:
+  <PATCH_ID>  The patch id to fetch it
+
+Options:
+      --repo <NADDR-NIP05-OR-SET>  Repository address in `naddr` format (`naddr1...`), NIP-05 format (`4rs.nl/n34` or `_@4rs.nl/n34`), or a set name like `kernel`
+  -o, --output <PATH>              Output directory for the patches. Default to the current directory
+```
+
+Fetches patches using their original patch ID. All fetched patches will be saved
+to the specified output directory (current directory by default). You can then
+apply or merge these patches into your branch as needed.