A multiplex gateway runs plugin discovery for every served profile, and each
discovery ran plugin_compat.scan_plugin (an ast.parse + two ast.walk passes per
file) over every external plugin: on an 11-profile host that was ~0.4s per
profile of identical work on the gateway boot path, ahead of adapter connect.
The scan result is now cached process-wide on the plugin dir's (relpath,
mtime_ns, size) signature whenever the loaded manifest is used; a changed file
rescans, a caller-supplied manifest bypasses the cache.
Measured over the 11-profile MCP discovery loop on the reporting host:
3.78s -> 3.01s; per empty profile 0.25-0.30s -> 0.11s.
teknium1