Clarify that sync of file deletion cannot work in inferred sync mode

Signed-off-by: Cornelius Weig <[email protected]>

Author: corneliusweig

docs/content/en/docs/how-tos/filesync/_index.md

@@ -42,6 +42,9 @@ And a `skaffold.yaml` with the following sync configuration:
 - The third rule synchronizes any `png`. For example if `assest/img.png` ↷ `assets/img.png` or `static-html/imgs/demo.png` ↷ `static/imgs/demo.png`.
 - The last rule enables synchronization for all `md` files below the `content/en`.
   For example, `content/en/sub/index.md` ↷ `content/sub/index.md` but _not_ `content/en_GB/index.md`.
+  
+Inferred sync mode only applies to modified and added files.
+File deletion will always cause a complete rebuild.
 
 ### Manual sync mode
 

docs/design_proposals/sync-improvements.md

@@ -304,6 +304,7 @@ Resolution: This is an implementation detail.
 
 - **implementation step 3** Set up automatic destination syncing and delete a local input file.
   Expect that the input file is also deleted in the container.
+  _Update_: This expectation cannot be met, because a deleted file is no longer contained in the inferred syncmap. Thus file deletion with inferred sync mode must trigger a rebuild.
 
 - **implementation step 4** Add a test case that that features builder plugin sync patterns.