fix(ui): align communications admin API paths with v0.17 module

[kkopanidis]

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change? (check one)

• Yes
• No

The PR fulfills these requirements:

• It's submitted to the ui-rewrite branch

Other information:

Conduit-UI still called legacy standalone-module Admin API paths after the communications consolidation. Push token listing, test send, and several email operations returned 404 against v0.17+ backends.

• Push: /pushNotifications/token → GET /push/tokens; /pushNotifications/token/:id → GET /push/tokens/:id (unwrap tokenDocuments); send routes → POST /push/send; multi-recipient test send fans out per user via POST /push/send
• Email: /email/externalTemplates → GET /email/templates/external; sync PATCH /email/syncExternalTemplates → POST /email/templates/external/sync; records GET /email/record → GET /email/emails with emailDocuments → records mapping; resend body { emailRecordId } → { id }; bulk template delete loops DELETE /email/templates/:id
• Email delivery status badge shows "Unavailable" (no admin REST route for status polling)
• Template upload to provider throws a clear error (no admin upload route)

Test plan

• Push settings (/push-notifications/settings): load and save config
• Push tokens (/push-notifications/tokens): list, search, pagination — requests hit /push/tokens
• Push test send (/push-notifications/test): single and multiple recipients
• Email settings (/email/settings): load and save
• Email templates: list, create, edit, delete single and bulk selected
• External templates tab loads; sync triggers POST /email/templates/external/sync
• Email send and records list; resend from record detail
• Upload template action shows error toast instead of 404
• SMS settings and test send unchanged (POST /sms/send)
• pnpm build passes locally