feat(bookmark): add prefix configuration for bookmark creation

- Add `prefix` option to `bookmark_create()` function for setting default bookmark names
- Add `bookmark.prefix` configuration option for global bookmark prefix defaults
- Update README with bookmark prefix usage examples

README.md

@@ -212,6 +212,11 @@ The plugin also provides `:Jdiff`, `:Jvdiff`, and `:Jhdiff` commands for diffing
       close_on_edit = false,                -- Close log buffer after editing a change
     },
 
+    -- Configure bookmark command
+    bookmark = {
+        prefix = ""
+    },
+
     -- Configure keymaps for command buffers
     keymaps = {
       -- Log buffer keymaps (set to nil to disable)
@@ -373,7 +378,20 @@ The `bookmark_create` function creates a new bookmark:
 
 ```lua
 local cmd = require("jj.cmd")
-cmd.bookmark_create()  -- Prompts for bookmark name, then prompts the revision
+cmd.bookmark_create()                               -- Prompts for bookmark name, then prompts the revision
+cmd.bookmark_create({ prefix = "feature/" })        -- Uses prefix for default bookmark name
+```
+
+You can also set a default bookmark prefix in the config:
+
+```lua
+require("jj").setup({
+  cmd = {
+    bookmark = {
+      prefix = "feature/"  -- Default prefix when creating bookmarks
+    }
+  }
+})
 ```
 
 The `bookmark_move` function moves an existing bookmark to a new revision:
@@ -442,6 +460,9 @@ diff.open_hsplit({ rev = "@-2" })   -- Horizontal split against @-2
             }
           }
         },
+        bookmark = {
+            prefix = "feat/"
+        },
         keymaps = {
           log = {
             checkout = "<CR>",

lua/jj/cmd/init.lua

@@ -43,6 +43,9 @@ local status_module = require("jj.cmd.status")
 --- @field open_pr_list? string|string[]
 --- @field bookmark? string|string[]
 
+--- @class jj.cmd.bookmark
+--- @field prefix? string Prefix to append when creating a bookmark
+
 --- @class jj.cmd.status.keymaps
 --- @field open_file? string|string[] Keymaps for the status command buffer, setting a keymap to nil will disable it
 --- @field restore_file? string|string[]
@@ -60,6 +63,7 @@ local status_module = require("jj.cmd.status")
 --- @class jj.cmd.opts
 --- @field describe? jj.cmd.describe
 --- @field log? jj.cmd.log
+--- @field bookmark? jj.cmd.bookmark
 --- @field keymaps? jj.cmd.keymaps Keymaps for the buffers containing the  of the commands
 ---
 --- @class jj.cmd.keymap_spec
@@ -88,6 +92,9 @@ M.config = {
 	log = {
 		close_on_edit = false,
 	},
+	bookmark = {
+		prefix = "",
+	},
 	keymaps = {
 		log = {
 			edit = "<CR>",
@@ -348,14 +355,19 @@ function M.rebase()
 end
 
 -- Jujutsu create bookmark
-function M.bookmark_create()
+--- @param opts? jj.cmd.bookmark The options for the bookmark command
+function M.bookmark_create(opts)
 	if not utils.ensure_jj() then
 		return
 	end
 
+	-- Try and get the bookmark from the params
+	local bookmark_prefix = (opts and opts.prefix) or (M.config.bookmark and M.config.bookmark.prefix) or ""
+
 	M.log({})
 	vim.ui.input({
 		prompt = "Bookmark name: ",
+		default = bookmark_prefix,
 	}, function(input)
 		if input then
 			-- Get the revset