docs: finish the whole-file-diff sweep across comments and RFCs

Codex's stale-prose pass found seven more spots still describing the
result diff as ALWAYS an applied contextual hunk, or a create/binary
overwrite as rendering "only the call-time card": the DiffCallView JSDoc
and the acp bridge diff-arm comment, the FsWriteOutcome.before and
readTextForDiff JSDoc, and three RFC lines. All now say: the result diff
is the applied change — a contextual hunk when there is a before-image,
else a whole-file diff (create / undiffable binary) — and a successful
mutation always returns the result diff so the model-facing text can't
clobber it. Regenerate the cordis catalog (source line shift).

packages/ui/acp/src/index.ts

@@ -1170,10 +1170,12 @@ function toolResultUpdate(callId: CallId, view: ToolResultView, isError: boolean
         ...view.title !== undefined ? { title: view.title } : {},
       }
     case 'diff': {
-      // A result-time applied-hunk diff: emit one `{ type: 'diff' }` content block
-      // per hunk (mirroring the call-side diff arm). `tool_call_update.content`
-      // REPLACES the call's content in an editor, so these hunks supersede the
-      // call-time whole-file snippet the pending card installed.
+      // A result-time diff: emit one `{ type: 'diff' }` content block per entry
+      // (an applied hunk for an edit/overwrite, or a whole-file diff for a
+      // create), mirroring the call-side diff arm. `tool_call_update.content`
+      // REPLACES the call's content in an editor, so this result diff supersedes
+      // the diff the pending card installed (and keeps the model-facing result
+      // text from clobbering it).
       const content: AcpToolCallContent[] = view.diffs.map(d => ({ type: 'diff', path: d.path, oldText: d.oldText, newText: d.newText }))
       return {
         sessionUpdate: 'tool_call_update',