feat(desktop): hydrate commands when repainting inert composer text

Two repaint sites hand the editor text that is finished rather than
mid-keystroke: the main composer's programmatic draft writes (restore,
insert, history recall) and the inline edit composer opening a sent
message. Both now render with `trailingCommitted`, so a command ending
that text chips instead of reading as a half-typed token — the edit
composer in particular showed plain text for a message the transcript
had just rendered with a pill.

Regression tests cover the paste path: a command ending the paste, one
named mid-prose beside a ref, a path left alone, a paste landing against
a word, and one landing after an existing chip.

apps/desktop/src/app/chat/composer/hooks/use-composer-draft.ts

@@ -121,7 +121,7 @@ export function useComposerDraft({
       const editor = editorRef.current
 
       if (editor) {
-        renderComposerContents(editor, next)
+        renderComposerContents(editor, next, { trailingCommitted: true })
         placeCaretEnd(editor)
       }
 
@@ -265,7 +265,7 @@ export function useComposerDraft({
       const editor = editorRef.current
 
       if (editor && document.activeElement !== editor && composerPlainText(editor) !== text) {
-        renderComposerContents(editor, text)
+        renderComposerContents(editor, text, { trailingCommitted: true })
       }
 
       if (isBrowsingHistory(sessionIdRef.current) || queueEditRef.current) {

apps/desktop/src/app/chat/composer/rich-editor.test.ts

@@ -230,6 +230,82 @@ describe('insertComposerContentsAtCaret', () => {
 
     editor.remove()
   })
+
+  // A directive typed by hand chips; the same directive pasted has to chip too,
+  // or copy/pasting a prompt silently drops every command in it.
+  it('chips a pasted slash command, including one that ends the paste', () => {
+    const editor = document.createElement('div')
+    editor.dataset.slot = RICH_INPUT_SLOT
+    document.body.append(editor)
+    caretIn(editor)
+
+    insertComposerContentsAtCaret(editor, '/some-skill')
+
+    expect(editor.querySelector('[data-slash-kind]')?.getAttribute('data-ref-text')).toBe('/some-skill')
+    // Committed pills carry the trailing space the typed path appends, so a
+    // later full re-render doesn't read the token as half-typed.
+    expect(composerPlainText(editor)).toBe('/some-skill ')
+
+    editor.remove()
+  })
+
+  it('chips a skill named mid-paste alongside a ref', () => {
+    const editor = document.createElement('div')
+    editor.dataset.slot = RICH_INPUT_SLOT
+    document.body.append(editor)
+    caretIn(editor)
+
+    insertComposerContentsAtCaret(editor, 'clean @file:`a.ts` with /some-skill then ship')
+
+    expect(editor.querySelectorAll('[data-slash-kind]').length).toBe(1)
+    expect(editor.querySelectorAll('[data-ref-kind="file"]').length).toBe(1)
+    expect(composerPlainText(editor)).toBe('clean @file:`a.ts` with /some-skill then ship')
+
+    editor.remove()
+  })
+
+  it('leaves a pasted path alone — /usr/local is not a command', () => {
+    const editor = document.createElement('div')
+    editor.dataset.slot = RICH_INPUT_SLOT
+    document.body.append(editor)
+    caretIn(editor)
+
+    insertComposerContentsAtCaret(editor, 'see /usr/local/bin and /goal ship it')
+
+    expect(editor.querySelector('[data-slash-kind]')).toBeNull()
+    expect(composerPlainText(editor)).toBe('see /usr/local/bin and /goal ship it')
+
+    editor.remove()
+  })
+
+  it('does not chip a command pasted against a word — foo/clean is not a command', () => {
+    const editor = document.createElement('div')
+    editor.dataset.slot = RICH_INPUT_SLOT
+    editor.textContent = 'foo'
+    document.body.append(editor)
+    caretIn(editor)
+
+    insertComposerContentsAtCaret(editor, '/some-skill')
+
+    expect(editor.querySelector('[data-slash-kind]')).toBeNull()
+    expect(composerPlainText(editor)).toBe('foo/some-skill')
+
+    editor.remove()
+  })
+
+  it('chips a command pasted right after an existing chip', () => {
+    const editor = document.createElement('div')
+    editor.dataset.slot = RICH_INPUT_SLOT
+    editor.append(refChipElement('file', '`a.ts`'))
+    document.body.append(editor)
+    caretIn(editor)
+
+    insertComposerContentsAtCaret(editor, '/some-skill')
+
+    expect(editor.querySelector('[data-slash-kind]')).not.toBeNull()
+
+    editor.remove()
+  })
 })
 
 describe('replaceBeforeCaret', () => {

apps/desktop/src/components/assistant-ui/thread/user-edit-composer.tsx

@@ -168,7 +168,7 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
       const editor = editorRef.current
 
       if (editor) {
-        renderComposerContents(editor, next)
+        renderComposerContents(editor, next, { trailingCommitted: true })
         placeCaretEnd(editor)
       }
 
@@ -187,7 +187,11 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
       editor &&
       (editor.childNodes.length === 0 || (document.activeElement !== editor && composerPlainText(editor) !== draft))
     ) {
-      renderComposerContents(editor, draft)
+      // Inert by construction — this repaints on mount or when the editor
+      // isn't the one being typed into. A message opened for edit is finished
+      // text, so a `/command` ending it is committed and chips, matching how
+      // the transcript rendered that same message a moment ago.
+      renderComposerContents(editor, draft, { trailingCommitted: true })
 
       if (document.activeElement === editor) {
         placeCaretEnd(editor)