ship the Vim keymap preset

T-65 — the capstone of the Vim epic. assets/keymaps/vim.yaml binds the
muscle-memory set guarded on vim.normal/insert/visual: hjkl/w/b/e/0/$/^/
gg/G motions, x/dd/dw/D/yy/p/P/cc/cw edits, i/a/I/A/o/O insert entries,
v + d/y/c in visual, Esc back to normal, and counts via the matcher. App
shortcuts (palette, find, zoom) are carried in the preset so they survive
under Vim.

The editor now feeds Shift chords to the matcher (Vim's capitals: G, D,
A, P, $) while still bubbling Ctrl/Alt/Meta to the global handler. The
keybindings-ui stub gains palette commands (`Keymap: Vim` / `Keymap:
Default`) to switch presets — the user-facing way to turn Vim on.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

assets/keymaps/vim.yaml

@@ -0,0 +1,169 @@
+# clide Vim keymap preset (T-65).
+#
+# Modal editing built on the keymap sequence layer (D-82). The Vim mode
+# service (builtin.vim) publishes vim.normal / vim.insert / vim.visual
+# scope flags; bindings here are guarded on them. Motions/edits resolve to
+# `command:editor.vim.<action>`, which the editor applies to the buffer
+# (read-only in command mode so keys never type); mode changes resolve to
+# `command:vim.mode.<mode>`.
+#
+# Notation (D-82): `+` joins a chord, a space sequences (`d d`), a YAML
+# list alternates (`[d, x]`). Repeat counts (`5j`) are captured by the
+# matcher — no binding needed.
+#
+# Scope: the muscle-memory set, not bit-exact Vim. cw/$/^ are
+# approximations; see vim_edit_ops.dart.
+
+name: vim
+
+bindings:
+  # ---- App shortcuts (shared with the default preset) -----------------
+  # Modified chords bubble past the editor to the global handler, so these
+  # keep working with the editor focused and under every mode.
+  - intent: palette.open
+    keys: [ctrl+shift+p, meta+shift+p]
+  - intent: palette.selectNext
+    keys: [down, ctrl+n]
+    when: palette.open
+  - intent: palette.selectPrevious
+    keys: [up, ctrl+p]
+    when: palette.open
+  - intent: palette.accept
+    keys: enter
+    when: palette.open
+  - intent: dismiss
+    keys: escape
+    when: palette.open
+  - intent: quickOpen.open
+    keys: [ctrl+p, meta+p]
+    when: "!palette.open"
+  - intent: quickOpen.selectNext
+    keys: [down, ctrl+n]
+    when: quickOpen.open
+  - intent: quickOpen.selectPrevious
+    keys: up
+    when: quickOpen.open
+  - intent: quickOpen.accept
+    keys: enter
+    when: quickOpen.open
+  - intent: dismiss
+    keys: escape
+    when: quickOpen.open
+  - intent: findInFiles.open
+    keys: [ctrl+shift+f, meta+shift+f]
+  - intent: focus.nextPanel
+    keys: f6
+  - intent: focus.previousPanel
+    keys: shift+f6
+  - intent: text.scaleIncrease
+    keys: [ctrl+equal, ctrl+shift+equal, meta+equal, meta+shift+equal]
+  - intent: text.scaleDecrease
+    keys: [ctrl+minus, meta+minus]
+  - intent: text.scaleReset
+    keys: [ctrl+0, meta+0]
+
+  # ---- Mode transitions ------------------------------------------------
+  - intent: command:vim.mode.visual
+    keys: v
+    when: vim.normal
+  - intent: command:vim.mode.normal
+    keys: escape
+    when: "vim.insert || vim.visual"
+
+  # ---- Insert entry (normal → insert), positioned by the editor --------
+  - intent: command:editor.vim.insert
+    keys: i
+    when: vim.normal
+  - intent: command:editor.vim.append
+    keys: a
+    when: vim.normal
+  - intent: command:editor.vim.insertLineStart
+    keys: shift+i # I
+    when: vim.normal
+  - intent: command:editor.vim.appendLineEnd
+    keys: shift+a # A
+    when: vim.normal
+  - intent: command:editor.vim.openBelow
+    keys: o
+    when: vim.normal
+  - intent: command:editor.vim.openAbove
+    keys: shift+o # O
+    when: vim.normal
+
+  # ---- Motions (normal + visual) ---------------------------------------
+  - intent: command:editor.vim.left
+    keys: h
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.down
+    keys: j
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.up
+    keys: k
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.right
+    keys: l
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.wordForward
+    keys: w
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.wordBackward
+    keys: b
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.wordEnd
+    keys: e
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.lineStart
+    keys: "0"
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.lineEnd
+    keys: shift+4 # $
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.firstNonBlank
+    keys: shift+6 # ^
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.docStart
+    keys: "g g" # gg
+    when: "vim.normal || vim.visual"
+  - intent: command:editor.vim.docEnd
+    keys: shift+g # G
+    when: "vim.normal || vim.visual"
+
+  # ---- Normal-mode edits ----------------------------------------------
+  - intent: command:editor.vim.deleteChar
+    keys: x
+    when: vim.normal
+  - intent: command:editor.vim.deleteLine
+    keys: "d d"
+    when: vim.normal
+  - intent: command:editor.vim.deleteWord
+    keys: "d w"
+    when: vim.normal
+  - intent: command:editor.vim.deleteToEnd
+    keys: shift+d # D
+    when: vim.normal
+  - intent: command:editor.vim.changeLine
+    keys: "c c"
+    when: vim.normal
+  - intent: command:editor.vim.changeWord
+    keys: "c w"
+    when: vim.normal
+  - intent: command:editor.vim.yankLine
+    keys: "y y"
+    when: vim.normal
+  - intent: command:editor.vim.paste
+    keys: p
+    when: vim.normal
+  - intent: command:editor.vim.pasteBefore
+    keys: shift+p # P
+    when: vim.normal
+
+  # ---- Visual-mode operators ------------------------------------------
+  - intent: command:editor.vim.visualDelete
+    keys: [d, x]
+    when: vim.visual
+  - intent: command:editor.vim.visualYank
+    keys: y
+    when: vim.visual
+  - intent: command:editor.vim.visualChange
+    keys: c
+    when: vim.visual