Correct stale claims in menu jsonc headers and bar README

Providers never returned JSON rows: they are shell-defined row sources
emitting tab-delimited lines, and extensions cannot declare new names.
bar.shellQuote moved to Util.qml, and the UpperCamelCase widget id
migration no longer exists.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

shell/plugins/bar/README.md

@@ -160,8 +160,7 @@ Widgets receive `bar` (the shell root), `moduleName` (string), and `settings` (o
 - `bar.position` — `"top" | "bottom" | "left" | "right"`
 - `bar.vertical` — boolean shortcut
 - `bar.barSize` — 26 horizontal / 28 vertical
-- `bar.run(command)` — fire-and-forget bash exec
-- `bar.shellQuote(value)` — safe shell-quote a string
+- `bar.run(command)` — fire-and-forget bash exec (quote arguments with `Util.shellQuote` from `qs.Commons`)
 - `bar.showTooltip(target, text)` / `bar.hideTooltip(target)` — shared tooltip popup
 - `bar.requestPopout(owner)` / `bar.releasePopout(owner)` — one-popup-at-a-time coordinator
 
@@ -171,9 +170,7 @@ richer popup plugins live in feature directories such as `../panels/audio/`,
 `../panels/network/`, and `../agents/`; and feature plugins such as
 `omarchy.menu` and `omarchy.media` declare their bar-widget entry points in their own
 `manifest.json`. Bar layout ids are namespaced, e.g. `omarchy.audio`,
-`omarchy.network`, and `omarchy.clock`. Older UpperCamelCase ids such as
-`AudioPanel` and `Clock` are migrated forward; new configs should use the
-namespaced ids.
+`omarchy.network`, and `omarchy.clock`.
 
 Third-party widgets ship as separate plugins under
 `~/.config/omarchy/plugins/<plugin-id>/` with their own `manifest.json`