Second module of the tabs.js split (after the roster keystone). The
P3RM1SS10NS tab — the per-agent capabilities + tool-groups matrices — is
the cleanest leaf: six contiguous functions with no module-scoped state
(each render builds fresh from the fetched payload) and no cross-domain
references except the agent roster, which it now imports from state.js.
Moves applyCapabilitiesChanged / applyToolGroupsChanged (the live-update
handlers wired into the entry's mutation dispatch table) and
fetchAndRenderCapabilities / fetchAndRenderToolGroups (called on tab
activation) into a new permissions.js, exporting those four; the two
renderers stay module-private. tabs.js imports the four — the dispatch
table and tab-activation call-sites resolve unchanged.
Behaviour-preserving: pure code motion. esbuild inlines permissions.js
into the tabs.js bundle, so the static output is unchanged. Build green;
tabs.js drops 258 lines.
