feat: add vici dial controls from UI (#563)

* ViciDial Working

* feat(telephony): add FreeSWITCH provider to upstream-PBX seam

Generalize the upstream-PBX capture and control paths to dispatch by
provider. FreeSWITCH bridges in with X-PBX-* headers and is driven over
the Event Socket Library (uuid_kill / uuid_transfer) by the channel UUID,
alongside the existing VICIdial ra_call_control path.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* add vici specific configs

* feat(telephony): env-based VICIdial config + address3 post-call routing

Move VICIdial agent/non-agent API and FreeSWITCH ESL connection settings
out of hardcoded POC values into environment variables so the same image
works against a PBX on another server.

Add VICIdial update_lead forwarding: X-VICI-UPDATE-LEAD_* extracted
variables are mapped to lead columns and pushed via the non-agent API
before a transfer, with reserved API-control params dropped.

Add hardcoded address3 disposition routing (Y/N -> in-group transfer,
else hang up) and a synchronous final variable extraction so the
transfer path sees the freshest conversation state. Skip upstream_pbx
capture on non-PJSIP channels to avoid Asterisk 500s.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* chore: run formatter

* feat: make vici configurable from UI

* chore: clean up PR

* fix: incorporate review comments

* chore: incorporate review comments

* chore: generate client

* chore: incporporate review comments

* chore: incorporate review comments

---------

Co-authored-by: Dograh POC <payment@dograh.com>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

api/services/telephony/external_pbx.py

@@ -0,0 +1,43 @@
+"""Provider-neutral helpers for external-PBX workflow mappings."""
+
+from __future__ import annotations
+
+from typing import Any, Iterable, Mapping
+
+
+def _read_path(context: Mapping[str, Any], path: str) -> Any:
+    normalized = path.strip()
+    if normalized.startswith("gathered_context."):
+        normalized = normalized.removeprefix("gathered_context.")
+    current: Any = context
+    for part in normalized.split("."):
+        if not isinstance(current, Mapping):
+            return None
+        current = current.get(part)
+    if current is None and "." not in normalized:
+        extracted = context.get("extracted_variables")
+        if isinstance(extracted, Mapping):
+            current = extracted.get(normalized)
+    return current
+
+
+def resolve_external_pbx_field_mappings(
+    gathered_context: Mapping[str, Any] | None,
+    mappings: Iterable[Mapping[str, Any]] | None,
+) -> dict[str, str]:
+    """Return provider field -> non-empty gathered-context value."""
+
+    context = gathered_context or {}
+    resolved: dict[str, str] = {}
+    for mapping in mappings or []:
+        context_path = str(mapping.get("context_path", "")).strip()
+        destination_field = str(mapping.get("destination_field", "")).strip()
+        if not context_path or not destination_field:
+            continue
+        value = _read_path(context, context_path)
+        if value is None:
+            continue
+        text = str(value).strip()
+        if text:
+            resolved[destination_field] = text
+    return resolved