Pure functions for the FTPS file source: file selection, which failures to
retry and error values. No I/O.

Pure functions for IMAP message parsing.
No I/O, no side effects.

TLS trust settings shared by the SMTP and IMAP adapters, as Angus Mail
session properties.

Pure functions for SMTP email preparation and validation.
No I/O, no side effects.

Pure functions for the SOAP 1.1 client: operation settings, the request
envelope, reading the response or fault, which failures to retry and error
values. No I/O.

The shell parses XML into elements of this shape, and serialises nothing:
the envelope is built here as a string.

  {:name "GetListsResult" :ns "http://tempuri.org/"
   :nil? false :text "" :children [element ...]}

Pure functions for Twilio API data transformation.
No I/O, no side effects.

Protocol definitions for external service adapters.

Defines three integration protocols:
- ISmtpProvider    — outbound email via SMTP
- IImapMailbox     — inbound email via IMAP
- ITwilioMessaging — Twilio SMS and WhatsApp messaging
- IFileSource      — remote files to import (FTPS)
- ISoapClient      — SOAP 1.1 operations (WCF services)

Malli validation schemas for external service adapters.

FTPS file source implementing IFileSource, on Apache Commons Net.

Explicit TLS (AUTH TLS, then PBSZ 0 and PROT P so the data channel is
encrypted too), passive mode, binary transfers. One connection per call. A
transient failure is retried with backoff; a 5xx reply is not.

Usage:
  (def source (create-ftps-source {:host "ftp.example.org"
                                   :username "import"
                                   :password "secret"}))
  (ports/list-files! source "/outbox" {:match #".*\.csv"})

IMAP mailbox adapter implementing IImapMailbox.

Uses Jakarta Mail for IMAP access. Connections are opened per-call and closed
in a finally block. Selection (unread, since, limit) runs as an IMAP SEARCH on
envelopes; content is read only for the selected messages.

Usage:
  (def mailbox (create-imap-mailbox
                 {:host "imap.gmail.com"
                  :port 993
                  :username "user@gmail.com"
                  :password "app-password"
                  :ssl? true}))
  (fetch-unread! mailbox)

SMTP transport adapter implementing ISmtpProvider.

Uses Jakarta Mail for SMTP communication. This adapter is positioned as a
transport-level provider — independent of the email lib's higher-level
abstraction (templating, job queuing, etc.).

Usage:
  (def provider (create-smtp-provider
                  {:host "smtp.gmail.com"
                   :port 587
                   :username "user@gmail.com"
                   :password "app-password"
                   :tls? true
                   :from "no-reply@example.com"}))
  (send-email! provider {:to "recipient@example.com"
                         :subject "Hello"
                         :body "World"})

SOAP 1.1 client implementing ISoapClient, on java.net.http and the JDK's
XML parser, for WCF services.

Operations are described in config rather than read from a WSDL: WCF's
defaults (SOAPAction namespace + contract + operation, request element named
after the operation) cover most, and :operations sets the rest.

Usage:
  (def ibabs (create-soap-client
              {:endpoint       "https://ibabs.example/api/v2/List.svc"
               :contract       "IList"
               :data-namespace "http://schemas.datacontract.org/2004/07/iBabs"
               :retry-faults   ["Unknown fault occured"]
               :operations     {:GetListEntries {:timeout-ms 60000}}}))
  (ports/call! ibabs :GetLists {:Sitename "town"})

Twilio messaging adapter implementing ITwilioMessaging.

Uses clj-http with Basic auth (account-sid + auth-token).
SMS and WhatsApp share the same Messages endpoint; the only difference
is the whatsapp: prefix added by core/twilio.

Usage:
  (def twilio (create-twilio-adapter
                {:account-sid "ACxxx"
                 :auth-token  "token"
                 :from-number "+15005550006"}))
  (send-sms! twilio {:to "+31612345678" :body "Hello!"})

Integrant lifecycle wiring for the external service adapters.

Registers init-key and halt-key! multimethods for:
  :wagoe.external/smtp   — SMTP transport provider
  :wagoe.external/imap   — IMAP mailbox reader
  :wagoe.external/twilio — Twilio SMS / WhatsApp
  :wagoe.external/ftps   — FTPS file source
  :wagoe.external/soap   — SOAP 1.1 client

All five keys are opt-in: add them to :active in config.edn to enable.
They are shipped in :inactive by default.

Retry and circuit breaker for the SMTP, IMAP and Twilio adapters, on the
same layer as the RPC client (`wagoe.platform.resilience`).

Both are opt-in. `:retries` retries only a call that never connected, since
one that connected may have sent the message. Off by default: these adapters
set no connect timeout, so an attempt against a host that drops packets can
take minutes. Pass a `:cache` for the breaker; it counts calls that got no
answer — never connected, or timed out.