feat: more llm provider options (google, mistral) (#28)

* feat: add google provider

* fix: default for google model

* feat: multiple providers

* fix: defaults from env for login form

* fix: add mistral to env files

* chore: delete unused code

* chore: revert database url to original

* fix: render default value for api key from env on server

* fix: type errors during compilation

---------

Co-authored-by: Vasily Zubarev <me@vas3k.ru>

lib/llm-providers.ts

@@ -0,0 +1,47 @@
+export const PROVIDERS = [
+  {
+    key: "openai",
+    label: "OpenAI",
+    apiKeyName: "openai_api_key",
+    modelName: "openai_model_name",
+    defaultModelName: "gpt-4o-mini",
+    apiDoc: "https://platform.openai.com/settings/organization/api-keys",
+    apiDocLabel: "OpenAI Platform Console",
+    placeholder: "sk-...",
+    help: {
+      url: "https://platform.openai.com/settings/organization/api-keys",
+      label: "OpenAI Platform Console"
+    },
+    logo: "/logo/openai.svg"
+  },
+  {
+    key: "google",
+    label: "Google",
+    apiKeyName: "google_api_key",
+    modelName: "google_model_name",
+    defaultModelName: "gemini-2.5-flash",
+    apiDoc: "https://aistudio.google.com/apikey",
+    apiDocLabel: "Google AI Studio",
+    placeholder: "...",
+    help: {
+      url: "https://aistudio.google.com/apikey",
+      label: "Google AI Studio"
+    },
+    logo: "/logo/google.svg"
+  },
+  {
+    key: "mistral",
+    label: "Mistral",
+    apiKeyName: "mistral_api_key",
+    modelName: "mistral_model_name",
+    defaultModelName: "mistral-medium-latest",
+    apiDoc: "https://admin.mistral.ai/organization/api-keys",
+    apiDocLabel: "Mistral Admin Console",
+    placeholder: "...",
+    help: {
+      url: "https://admin.mistral.ai/organization/api-keys",
+      label: "Mistral Admin Console"
+    },
+    logo: "/logo/mistral.svg"
+  },
+]