The runtime already registers nothing for an explicit empty include list
(fb1ec36a4b), but every CLI reader still coerced `[]` to "no filter":
`hermes mcp list` printed "all", `hermes mcp configure` and `hermes tools`
pre-checked every tool (so confirming the picker silently re-enabled all of
them), and a catalog reinstall pre-checked the manifest defaults over the
user's zero-tool choice.
`_tool_filters` now returns the list whenever the key holds a list; only an
absent/non-list key is None. The pickers and list output branch on `is not
None`, matching `tools/mcp_tool_registration.py`.
Fixes#12865. Builds on #13096 (@dingn42) and #52874 (@Bartok9).
teknium1