Network: grant the T18 principal actor.task.create (actor-task action) (#132)

ddiff --git a/server/identity/principals.js b/server/identity/principals.js
iindex 9ffeaaac..83fd0961 100644
---- a/server/identity/principals.js
++++ b/server/identity/principals.js
@@@ -214,6 +214,9 @@ const DEFAULT_GRANTS = [
      // (a usr_ subject) to Network's user id, then pushes as app 'watch' (openvibe-sdk/notifications).
      ['watch', 'identity.subject.resolve', SELF_AUDIENCE, []],
      ['watch', 'network.notifications.push', SELF_AUDIENCE, ['watch']],
++    // Plan T18 step 6: a watch's actor-task action gives Actor a task for the watch's owner. Watch names the owner in
++    // X-OV-Subject, so the task is the person's (their allowance and list) and Actor records Watch as `via`.
++    ['watch', 'actor.task.create', 'openvibe.actor', []],
      // Plan T13: OpenVibe.Services merges every authority's resource index (ADR-048 section 3): it reads each one's
      // GET /api/v1/resources under that authority's <id>.resource.read, with a token for that authority's audience.
      ['services', 'network.resource.read', SELF_AUDIENCE, []],
ddiff --git a/test/t18-grants.test.js b/test/t18-grants.test.js
nnew file mode 100644
iindex 00000000..b6b1a515
---- /dev/null
++++ b/test/t18-grants.test.js
@@@ -0,0 +1,25 @@
++/**
++ * OpenVibe.Watch's grants (plan T18): it publishes its events, resolves a watch's owner and pushes them a notification
++ * (step 4), and gives Actor a task for the owner (step 6, audience openvibe.actor). Each capability it holds is one
++ * the pinned contracts offer, active.
++ *
++ *   node test/t18-grants.test.js
++ */
++'use strict';
++const assert = require('assert');
++const contracts = require('openvibe-contracts');
++const principals = require('../server/identity/principals');
++
++const rows = principals.DEFAULT_GRANTS.filter((g) => g[0] === 'watch');
++const held = new Set(rows.map((g) => `${g[1]}@${g[2]}`));
++for (const want of [
++    '[email protected]',
++    '[email protected]',
++    `identity.subject.resolve@${principals.SELF_AUDIENCE}`,
++    `network.notifications.push@${principals.SELF_AUDIENCE}`,
++]) assert.ok(held.has(want), `watch holds ${want}`);
++for (const g of rows) {
++    const cap = contracts.capabilities.get(g[1]);
++    assert.ok(cap && cap.status === 'active', `${g[1]} is an active capability`);
++}
++console.log(`t18 grants: ${rows.length}`);