licence: record gossamer as MPL-2.0 component in Rule 3a example

gossamer is a sole-owner component (not shared with Joshua), so it is MPL-2.0
even when used by the AGPL paint.type work. An AGPL label on a gossamer file is
drift, not policy. Added to the Rule 3a worked example to prevent recurrence.

Author: claude

LICENCE-POLICY.adoc

@@ -76,10 +76,13 @@ shared project**.
 
 [example]
 ====
-`blueshift` — a specialist canvas tool authored by Jonathan, in its own
-*unshared* repo — is `MPL-2.0`. `paint.type` (shared with Joshua) is
-`AGPL-3.0-or-later`. When `paint.type` uses `blueshift`, the `blueshift`
-files stay `MPL-2.0`; only the `paint.type` work as a whole is AGPL.
+`blueshift` (a specialist canvas tool) and `gossamer` (a backend/capabilities
+component) are authored by Jonathan in their own *unshared* repos, so they are
+`MPL-2.0`. `paint.type` (shared with Joshua) is `AGPL-3.0-or-later`. When
+`paint.type` uses `blueshift` or `gossamer`, those component files stay
+`MPL-2.0`; only the `paint.type` work as a whole is AGPL. (A component being
+*used by* an AGPL work never relicenses the component — so a `gossamer` file
+marked `AGPL-3.0-or-later` is drift, not policy.)
 ====
 
 This is exactly what MPL-2.0 is designed for: it is file-level (weak)