Add vim-style Ctrl+Shift+h/j/k/l block navigation and move launcher shortcut from Ctrl+Shift+k to Ctrl+Shift+x (#2909)

## Summary

This PR adds vim-style movement aliases for block navigation and updates
one conflicting
  shortcut.

  ## Changes

  - Added global keybindings:
    - `Ctrl+Shift+h` -> move focus left
    - `Ctrl+Shift+j` -> move focus down
    - `Ctrl+Shift+k` -> move focus up
    - `Ctrl+Shift+l` -> move focus right
  - Kept existing arrow-based movement:
    - `Ctrl+Shift+ArrowUp/Down/Left/Right`
  - **Changed launcher shortcut**:
    - from `Ctrl+Shift+k`
    - to `Ctrl+Shift+x`

  ## Why `k` changed to `x`

`Ctrl+Shift+k` is now used for vim-style upward movement (`k` = up), so
launcher replace
  needed a new binding.
`Ctrl+Shift+x` was chosen to avoid collisions with existing Wave global
keybindings.

  ## Config / behavior notes

- `app:disablectrlshiftarrows` now disables both block-navigation sets:
    - Arrow keys
    - `h/j/k/l` aliases
  - It does **not** disable `Ctrl+Shift+x` (launcher replace).

  ## Docs updated

  - `docs/docs/keybindings.mdx`
    - Added `Ctrl+Shift+h/j/k/l` navigation display
    - Updated launcher replace shortcut to `Ctrl+Shift+x`
  - `docs/docs/config.mdx`
- Clarified `app:disablectrlshiftarrows` scope to include `Arrow` +
`h/j/k/l`

Author: jfeust

docs/docs/config.mdx

@@ -41,7 +41,7 @@ wsh editconfig
 | app:ctrlvpaste                       | bool     | On Windows/Linux, when null (default) uses Control+V on Windows only. Set to true to force Control+V on all non-macOS platforms, false to disable the accelerator. macOS always uses Command+V regardless of this setting                                     |
 | app:confirmquit <VersionBadge version="v0.14" />                     | bool     | Set to false to disable the quit confirmation dialog when closing Wave Terminal (defaults to true, requires app restart)                                                                                                                                      |
 | app:hideaibutton <VersionBadge version="v0.14" />                    | bool     | Set to true to hide the AI button in the tab bar (defaults to false)                                                                                                                                                                                          |
-| app:disablectrlshiftarrows <VersionBadge version="v0.14" />          | bool     | Set to true to disable Ctrl+Shift+Arrow keybindings for block navigation (defaults to false)                                                                                                                                                                  |
+| app:disablectrlshiftarrows <VersionBadge version="v0.14" />          | bool     | Set to true to disable Ctrl+Shift block-navigation keybindings (`Arrow` and `h/j/k/l`) (defaults to false)                                                                                                                                                    |
 | app:disablectrlshiftdisplay <VersionBadge version="v0.14" />         | bool     | Set to true to disable the Ctrl+Shift visual indicator display (defaults to false)                                                                                                                                                                            |
 | ai:preset                            | string   | the default AI preset to use                                                                                                                                                                                                                                  |
 | ai:baseurl                           | string   | Set the AI Base Url (must be OpenAI compatible)                                                                                                                                                                                                               |

docs/docs/keybindings.mdx

@@ -42,8 +42,8 @@ Chords are shown with a + between the keys. You have 2 seconds to hit the 2nd ch
 | <Kbd k="Ctrl:Shift"/>                             | Show block numbers                                                                                                                                     |
 | <Kbd k="Ctrl:Shift:0"/>                           | Focus WaveAI input                                                                                                                                     |
 | <Kbd k="Ctrl:Shift:1-9"/>                         | Switch to block number                                                                                                                                 |
-| <Kbd k="Ctrl:Shift:Arrows"/>                      | Move left, right, up, down between blocks                                                                                                              |
-| <Kbd k="Ctrl:Shift:k"/>                           | Replace the current block with a launcher block                                                                                                        |
+| <Kbd k="Ctrl:Shift:Arrows"/> / <Kbd k="Ctrl:Shift:h/j/k/l"/> | Move left, right, up, down between blocks                                                                                                              |
+| <Kbd k="Ctrl:Shift:x"/>                           | Replace the current block with a launcher block                                                                                                        |
 | <Kbd k="Cmd:1-9"/>                                | Switch to tab number                                                                                                                                   |
 | <Kbd k="Cmd:["/> / <Kbd k="Shift:Cmd:["/>         | Switch tab left                                                                                                                                        |
 | <Kbd k="Cmd:]"/> / <Kbd k="Shift:Cmd:]"/>         | Switch tab right                                                                                                                                       |

frontend/app/store/keymodel.ts

@@ -585,7 +585,40 @@ function registerGlobalKeys() {
         switchBlockInDirection(NavigateDirection.Right);
         return true;
     });
+    // Vim-style aliases for block focus navigation.
+    globalKeyMap.set("Ctrl:Shift:h", () => {
+        const disableCtrlShiftArrows = globalStore.get(getSettingsKeyAtom("app:disablectrlshiftarrows"));
+        if (disableCtrlShiftArrows) {
+            return false;
+        }
+        switchBlockInDirection(NavigateDirection.Left);
+        return true;
+    });
+    globalKeyMap.set("Ctrl:Shift:j", () => {
+        const disableCtrlShiftArrows = globalStore.get(getSettingsKeyAtom("app:disablectrlshiftarrows"));
+        if (disableCtrlShiftArrows) {
+            return false;
+        }
+        switchBlockInDirection(NavigateDirection.Down);
+        return true;
+    });
     globalKeyMap.set("Ctrl:Shift:k", () => {
+        const disableCtrlShiftArrows = globalStore.get(getSettingsKeyAtom("app:disablectrlshiftarrows"));
+        if (disableCtrlShiftArrows) {
+            return false;
+        }
+        switchBlockInDirection(NavigateDirection.Up);
+        return true;
+    });
+    globalKeyMap.set("Ctrl:Shift:l", () => {
+        const disableCtrlShiftArrows = globalStore.get(getSettingsKeyAtom("app:disablectrlshiftarrows"));
+        if (disableCtrlShiftArrows) {
+            return false;
+        }
+        switchBlockInDirection(NavigateDirection.Right);
+        return true;
+    });
+    globalKeyMap.set("Ctrl:Shift:x", () => {
         const blockId = getFocusedBlockId();
         if (blockId == null) {
             return true;