fix(api): sanitize error responses in HTTP handlers

src/voice/_index.yaml

@@ -65,6 +65,14 @@ entries:
         description: Given page context (page, params), returns the agent ID to use for this page
 
   # ── Libraries ──
+  - name: api_error
+    kind: library.lua
+    meta:
+      comment: Sanitized API error responses with server-side logging
+    source: file://api_error.lua
+    modules:
+      - logger
+
   - name: agents
     kind: library.lua
     source: file://agents.lua
@@ -92,6 +100,7 @@ entries:
     source: file://ask.lua
     method: handler
     imports:
+      api_error: wippy-swiss.voice:api_error
       session: wippy-swiss.voice:session
       context: wippy-swiss.voice:context
       agents: wippy-swiss.voice:agents
@@ -124,6 +133,8 @@ entries:
     kind: function.lua
     source: file://tts_token.lua
     method: handler
+    imports:
+      api_error: wippy-swiss.voice:api_error
     modules:
       - http
       - json

src/voice/api_error.lua

@@ -0,0 +1,17 @@
+local log = require("logger"):named("wippy-swiss.voice")
+
+local api_error = {}
+
+function api_error.fail(res, status, message, err)
+    if err ~= nil then
+        log:error(message, { error = tostring(err) })
+    end
+
+    res:set_status(status)
+    res:write_json({
+        success = false,
+        error = message
+    })
+end
+
+return api_error

src/voice/ask.lua

@@ -7,6 +7,7 @@ local security = require("security")
 local time = require("time")
 local logger = require("logger"):named("voice")
 local contract = require("contract")
+local api_error = require("api_error")
 
 local session = require("session")
 local context = require("context")
@@ -142,8 +143,7 @@ local function handler()
     )
 
     if not ok then
-        res:set_status(http.STATUS.INTERNAL_ERROR)
-        res:write_json({ success = false, error = "send failed: " .. tostring(send_err) })
+        api_error.fail(res, http.STATUS.INTERNAL_ERROR, "send failed", send_err)
         return
     end
 

src/voice/tts_token.lua

@@ -3,6 +3,7 @@ local json = require("json")
 local env = require("env")
 local security = require("security")
 local http_client = require("http_client")
+local api_error = require("api_error")
 
 local NS = "voice.env:"
 
@@ -82,8 +83,7 @@ local function handler()
 
     local tts, tts_err = get_tts_config()
     if not tts then
-        res:set_status(http.STATUS.INTERNAL_ERROR)
-        res:write_json({ success = false, error = tts_err })
+        api_error.fail(res, http.STATUS.INTERNAL_ERROR, tts_err, nil)
         return
     end