jj-duplicate: add page (#19140)

Signed-off-by: Emmanuel Ferdman <[email protected]>

Author: emmanuel-ferdman

pages/common/jj-duplicate.md

@@ -0,0 +1,32 @@
+# jj duplicate
+
+> Create new changes with the same content as existing ones.
+> More information: <https://jj-vcs.github.io/jj/latest/cli-reference/#jj-duplicate>.
+
+- Duplicate the current revision onto its existing parent:
+
+`jj duplicate`
+
+- Duplicate a specific revision onto its existing parent:
+
+`jj duplicate {{revset}}`
+
+- Duplicate a revision onto a different parent:
+
+`jj duplicate --destination {{dest_revset}} {{revset}}`
+
+- Duplicate a revision and insert it **after** other revision(s):
+
+`jj duplicate --insert-after {{after_revset}} {{revset}}`
+
+- Duplicate a revision and insert it **before** other revision(s):
+
+`jj duplicate --insert-before {{before_revset}} {{revset}}`
+
+- Duplicate onto multiple parents (creates a merge commit):
+
+`jj duplicate --destination {{destination1}} --destination {{destination2}} {{revset}}`
+
+- Duplicate multiple revisions:
+
+`jj duplicate {{revset1 revset2 ...}}`