feat(settings): add OpenAI/Google API key support and unified ModelId type

- Add OpenAI API key storage to store-api-key handler
- Include Google/OpenAI key status in credentials API responses
- Add unified ModelId type for Claude, Codex, Cursor, OpenCode, and dynamic providers
- Update PhaseModelEntry to support all provider model types

libs/types/src/index.ts

@@ -79,6 +79,7 @@ export {
   type ModelAlias,
   type CodexModelId,
   type AgentModel,
+  type ModelId,
 } from './model.js';
 
 // Event types

libs/types/src/model.ts

@@ -1,6 +1,9 @@
 /**
  * Model alias mapping for Claude models
  */
+import type { CursorModelId } from './cursor-models.js';
+import type { OpencodeModelId } from './opencode-models.js';
+
 export const CLAUDE_MODEL_MAP: Record<string, string> = {
   haiku: 'claude-haiku-4-5-20251001',
   sonnet: 'claude-sonnet-4-5-20250929',
@@ -74,3 +77,26 @@ export type CodexModelId = (typeof CODEX_MODEL_MAP)[keyof typeof CODEX_MODEL_MAP
  * Represents available models across providers
  */
 export type AgentModel = ModelAlias | CodexModelId;
+
+/**
+ * Dynamic provider model IDs discovered at runtime (provider/model format)
+ */
+export type DynamicModelId = `${string}/${string}`;
+
+/**
+ * Provider-prefixed model IDs used for routing
+ */
+export type PrefixedCursorModelId = `cursor-${string}`;
+export type PrefixedOpencodeModelId = `opencode-${string}`;
+
+/**
+ * ModelId - Unified model identifier across providers
+ */
+export type ModelId =
+  | ModelAlias
+  | CodexModelId
+  | CursorModelId
+  | OpencodeModelId
+  | DynamicModelId
+  | PrefixedCursorModelId
+  | PrefixedOpencodeModelId;

libs/types/src/settings.ts

@@ -6,7 +6,7 @@
  * (for file I/O via SettingsService) and the UI (for state management and sync).
  */
 
-import type { ModelAlias, AgentModel, CodexModelId } from './model.js';
+import type { ModelAlias, ModelId } from './model.js';
 import type { CursorModelId } from './cursor-models.js';
 import { CURSOR_MODEL_MAP, getAllCursorModelIds } from './cursor-models.js';
 import type { OpencodeModelId } from './opencode-models.js';
@@ -114,8 +114,8 @@ const DEFAULT_CODEX_ADDITIONAL_DIRS: string[] = [];
  * - Cursor models: Handle thinking internally
  */
 export interface PhaseModelEntry {
-  /** The model to use (Claude alias, Cursor model ID, or Codex model ID) */
-  model: ModelAlias | CursorModelId | CodexModelId;
+  /** The model to use (supports Claude, Cursor, Codex, OpenCode, and dynamic provider IDs) */
+  model: ModelId;
   /** Extended thinking level (only applies to Claude models, defaults to 'none') */
   thinkingLevel?: ThinkingLevel;
   /** Reasoning effort level (only applies to Codex models, defaults to 'none') */