feat: Phase 4 — topic CRUD UI in 'ניהול' tab

Adds a topics-management panel above the sources table. Admins can
create new legal domains (דיני עבודה, דין פלילי, נדל"ן) without
running SQL — slug + name + description + system prompt addendum
all live in one inline form. Per-row actions:

  ✏ Edit          — opens inline form with all fields except slug
                    (slug is locked post-create — the S3 layout
                    depends on it)
  👁 Toggle active — soft-disable: hides the topic from the user-facing
                    <select> while keeping data intact. Eye icon
                    flips between "השבת" and "הפעל"
  🗑 Delete       — hard-delete; only allowed when source_count=0.
                    Otherwise the UI directs the user to soft-disable
                    instead

Any topic mutation (create / rename / toggle / delete) invalidates
the cached _topics list so the user-facing dropdown re-fetches
immediately — admins don't have to refresh the page to see their
own changes.

Service.request() now distinguishes 4xx from 5xx upstream errors:
4xx is rethrown as BadRequest (so the user sees "slug already exists"
instead of a generic 500), 5xx stays as Error.

Backend: depends on shira-hermes commit 49503ca (admin topic
endpoints). No new migration — kb_topic schema from migration 001
is sufficient.

Description field in manifest was rewritten to Hebrew to match the
in-CRM scopeNames label ("מאגר ידע").

Refs Task Master #15

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

manifest.json

@@ -1,7 +1,7 @@
 {
     "name": "KnowledgeBase",
     "module": "KnowledgeBase",
-    "version": "0.6.0",
+    "version": "0.7.0",
     "acceptableVersions": [
         ">=8.0.0"
     ],
@@ -10,5 +10,5 @@
     ],
     "releaseDate": "2026-04-25",
     "author": "klear",
-    "description": "Knowledge Base — Israeli National Insurance law, regulations, and circulars. Hybrid search + ask-shira, powered by shira-hermes KB."
+    "description": "מאגר ידע — חוק הביטוח הלאומי, תקנות וחוזרים"
 }