feat(mcp): connect_migration: one-click card into the previous-system wizard (#1960)

* feat(mcp): gnubok_connect_migration: one-click connect card into the previous-system wizard

'Jag hade Fortnox' now gets the same feel as Skatteverket: the tool
returns the migration-wizard link for the named provider and renders
the connect-card widget (new migration branch: 'Hämta från Fortnox',
button opens the wizard that logs into the old system and fetches all
fiscal years plus invoices, customers, suppliers and documents). For
visma/bokio (no API export) the instructions order the SIE drop card
first and this card as the complement. Scope companies:read; skill
step 3 points at the tool instead of raw wizard links; ceiling 62.4K
to 63K documented.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* fix(mcp): 5-minute freshness hint on tools/list, widgets and prompts: the catalog changes with every deploy

The stateless-client CacheableResult hint on tools/list, resources/read
(widget HTML) and prompts/list was 1 hour. Claude.ai honors it, so for
up to an hour after a deploy the connector served a pre-deploy catalog:
a freshly shipped tool flapped in and out of the tool list depending on
which fetch hit the client cache, and two E2E runs dead-ended on
'tool does not exist' for a tool that was live server-side. These
payloads are static only within one deploy; 5 minutes bounds the stale
window.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Jakob Wennberg <311770904+jakobwennberg-oss@users.noreply.github.com>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

lib/auth/scope-catalog.ts

@@ -210,6 +210,7 @@ export const TOOL_SCOPE_MAP: Record<string, ApiKeyScope> = {
   gnubok_lookup_company:                  'companies:read',
   gnubok_connect_bank:                    'companies:read',
   gnubok_connect_skatteverket:            'companies:read',
+  gnubok_connect_migration:               'companies:read',
   gnubok_get_company_settings:            'companies:read',
   gnubok_update_company_settings:         'companies:write',
   // Transactions