feat(ui): rinomina Misure→Attività, textarea descrizione task, tool Testo annotazioni

- Navbar e breadcrumb: label "Misure" rinominata "Attività" (IT) / "Activities" (EN)
- Descrizione task: input sostituito con textarea multilinea + display whitespace-pre-wrap
- Annotation editor: nuovo tool "Testo" con fabric.IText (inline editing, serializzazione, viewer)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/frontend/flask_app/translations/en/LC_MESSAGES/messages.po

@@ -650,7 +650,7 @@ msgstr "NON-CONFORMING"
 #: templates/measure/task_complete.html:16
 #: templates/measure/task_execute.html:2 templates/measure/task_list.html:16
 msgid "Misure"
-msgstr "Measurements"
+msgstr "Activities"
 
 #: templates/components/navbar.html:55 templates/components/navbar.html:265
 #: templates/maker/recipe_editor.html:51 templates/maker/recipe_list.html:83
@@ -1069,7 +1069,11 @@ msgstr "Arrow"
 msgid "Rettangolo"
 msgstr "Rectangle"
 
-#: templates/maker/task_drawing.html:258
+#: templates/maker/task_drawing.html:261
+msgid "Testo"
+msgstr "Text"
+
+#: templates/maker/task_drawing.html:272
 msgid "Elimina selezionato"
 msgstr "Delete selected"