keymap: Update Prev to Previous for consistency (#25909)

Closes #10167

This is take 2 on https://github.com/zed-industries/zed/pull/2341 which
was closed due to lack of migrator.

This PR contains rename of following keymap actions: 
```sh
1. ["editor::GoToPrevHunk", { "center_cursor": true }] -> ["editor::GoToPreviousHunk", { "center_cursor": true }]
2. "editor::GoToPrevDiagnostic" -> "editor::GoToPreviousDiagnostic"
3. "editor::ContextMenuPrev" -> "editor::ContextMenuPrevious"
4. "search::SelectPrevMatch" -> "search::SelectPreviousMatch"
5. "file_finder::SelectPrev" -> "file_finder::SelectPrevious"
6. "menu::SelectPrev" -> "menu::SelectPrevious"
7. "editor::TabPrev" -> "editor::Backtab"
```

Release Notes:

- Renamed several keymap actions for consistency (e.g., `GoToPrevHunk` →
`GoToPreviousHunk`, `TabPrev` → `Backtab`). Your existing configured
keybindings will still work. You can click **"Backup and Update"** at
the top of your keymap file to easily update to the new actions.


Co-authored-by: Joseph T. Lyons <JosephTLyons@gmail.com>

crates/storybook/src/stories/picker.rs

@@ -114,10 +114,10 @@ impl PickerStory {
     pub fn new(window: &mut Window, cx: &mut App) -> Entity<Self> {
         cx.new(|cx| {
             cx.bind_keys([
-                KeyBinding::new("up", menu::SelectPrev, Some("picker")),
+                KeyBinding::new("up", menu::SelectPrevious, Some("picker")),
                 KeyBinding::new("pageup", menu::SelectFirst, Some("picker")),
                 KeyBinding::new("shift-pageup", menu::SelectFirst, Some("picker")),
-                KeyBinding::new("ctrl-p", menu::SelectPrev, Some("picker")),
+                KeyBinding::new("ctrl-p", menu::SelectPrevious, Some("picker")),
                 KeyBinding::new("down", menu::SelectNext, Some("picker")),
                 KeyBinding::new("pagedown", menu::SelectLast, Some("picker")),
                 KeyBinding::new("shift-pagedown", menu::SelectFirst, Some("picker")),