Add optional Nanobot plugin controls (#4396)

* feat: add optional nanobot features

* test: update azure install hint expectation

* fix: validate optional feature extras

maintainer edit: verify requested dependency extras before treating optional features as installed, propagate restart state from feature enablement, and align docs with the new plugins enable command.

* fix: bound optional feature installs

maintainer edit: make optional feature installs time out as a normal install failure instead of leaving the WebUI or CLI action waiting indefinitely.

* feat: slim optional channel dependencies

* fix: log optional install commands

* fix(webui): gate remote feature installs

* docs: clarify webhook plugin example

* fix(webui): harden optional feature installs

* fix: install optional deps without package fallback

* fix(cli): refine plugin feature controls

* fix(webui): count enabled nanobot features

* fix(webui): allow slow feature install routes

* fix(webui): allow disabling websocket channel

* fix(plugins): simplify optional feature controls

* fix(webui): polish apps catalog states

* fix(webui): confirm nanobot support installs

* fix(webui): polish nanobot install dialog

* fix(webui): suppress empty websocket handshakes

* fix(webui): clarify apps plugin summary

* fix(webui): localize workspace access copy

* fix(plugins): polish optional feature controls (#4691)

---------

Co-authored-by: Xubin Ren <52506698+Re-bin@users.noreply.github.com>

tests/utils/test_webui_websocket_logging.py

@@ -26,9 +26,12 @@ def test_websocket_handshake_noise_filter_suppresses_disconnects() -> None:
     filter_ = WebSocketHandshakeNoiseFilter()
     wrapped = RuntimeError("wrapped")
     wrapped.__cause__ = BrokenPipeError(32, "Broken pipe")
+    empty_handshake = RuntimeError("wrapped")
+    empty_handshake.__cause__ = EOFError("connection closed while reading HTTP request line")
 
     assert not filter_.filter(_log_record(OPENING_HANDSHAKE_FAILED_MESSAGE, BrokenPipeError()))
     assert not filter_.filter(_log_record(OPENING_HANDSHAKE_FAILED_MESSAGE, wrapped))
+    assert not filter_.filter(_log_record(OPENING_HANDSHAKE_FAILED_MESSAGE, empty_handshake))
 
 
 def test_websocket_handshake_noise_filter_keeps_real_errors() -> None: