Implement support for generic OpenAI api (#213)

* Implement support for generic OpenAI api

- Implements support to route requests to any openAI capable provider ( Deepsek, Qwen, VLLM, LM Studio, Ollama ).
- Keeps support for pure OpenAI and uses the new better responses api
- Uses the /chat/completions api for the generic providers
- If uri_base is not set, uses default implementation.

* Fix json handling and indentation

* Fix linter error indent

* Fix tests to set env vars

* Fix updating settings

* Change to prefix checking for OAI models

* FIX check model if custom uri is set

* Change chat to sync calls

Some local models don't support streaming. Revert to sync calls for generic OAI api

* Fix tests

* Fix tests

* Fix for gpt5 message extraction

- Finds the message output by filtering for "type" == "message" instead of assuming it's at index 0
- Safely extracts the text using safe navigation operators (&.)
- Raises a clear error if no message content is found
- Parses the JSON as before

* Add more langfuse logging

- Add Langfuse to auto categorizer and merchant detector
- Fix monitoring on streaming chat responses
- Add Langfuse traces also for model errors now

* Update app/models/provider/openai.rb

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>
Signed-off-by: soky srm <sokysrm@gmail.com>

* handle nil function results explicitly

* Exposing some config vars.

* Linter and nitpick comments

* Drop back to `gpt-4.1` as default for now

* Linter

* Fix for strict tool schema in Gemini

- This fixes tool calling in Gemini OpenAI api
- Fix for getTransactions function, page size is not used.

---------

Signed-off-by: soky srm <sokysrm@gmail.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>
Co-authored-by: Juan José Mata <juanjo.mata@gmail.com>

app/views/settings/hostings/_openai_settings.html.erb

@@ -16,8 +16,8 @@
                          "auto-submit-form-trigger-event-value": "blur"
                        } do |form| %>
   <%= form.password_field :openai_access_token,
-                          label: t(".label"),
-                          placeholder: t(".placeholder"),
+                          label: t(".access_token_label"),
+                          placeholder: t(".access_token_placeholder"),
                           value: (Setting.openai_access_token.present? ? "********" : nil),
                           autocomplete: "off",
                           autocapitalize: "none",
@@ -25,5 +25,27 @@
                           inputmode: "text",
                           disabled: ENV["OPENAI_ACCESS_TOKEN"].present?,
                           data: { "auto-submit-form-target": "auto" } %>
+
+  <%= form.text_field :openai_uri_base,
+                      label: t(".uri_base_label"),
+                      placeholder: t(".uri_base_placeholder"),
+                      value: Setting.openai_uri_base,
+                      autocomplete: "off",
+                      autocapitalize: "none",
+                      spellcheck: "false",
+                      inputmode: "url",
+                      disabled: ENV["OPENAI_URI_BASE"].present?,
+                      data: { "auto-submit-form-target": "auto" } %>
+
+  <%= form.text_field :openai_model,
+                      label: t(".model_label"),
+                      placeholder: t(".model_placeholder"),
+                      value: Setting.openai_model,
+                      autocomplete: "off",
+                      autocapitalize: "none",
+                      spellcheck: "false",
+                      inputmode: "text",
+                      disabled: ENV["OPENAI_MODEL"].present?,
+                      data: { "auto-submit-form-target": "auto" } %>
   <% end %>
 </div>