refactor(packages/coding-agent): migrated imports to pi-ai submodules

- Migrated Effort and THINKING_EFFORTS imports to @oh-my-pi/pi-ai/effort in CLI args and launch command files.
- Split model-registry dependencies across focused @oh-my-pi/pi-ai submodules instead of the root barrel export.

packages/coding-agent/src/cli/args.ts

@@ -1,7 +1,7 @@
 /**
  * CLI argument parsing and help display
  */
-import { type Effort, THINKING_EFFORTS } from "@oh-my-pi/pi-ai";
+import { type Effort, THINKING_EFFORTS } from "@oh-my-pi/pi-ai/effort";
 import { APP_NAME, CONFIG_DIR_NAME, logger } from "@oh-my-pi/pi-utils";
 import chalk from "chalk";
 import { parseEffort } from "../thinking";

packages/coding-agent/src/commands/launch.ts

@@ -2,7 +2,7 @@
  * Root command for the coding agent CLI.
  */
 
-import { THINKING_EFFORTS } from "@oh-my-pi/pi-ai";
+import { THINKING_EFFORTS } from "@oh-my-pi/pi-ai/effort";
 import { APP_NAME } from "@oh-my-pi/pi-utils";
 import { Args, Command, Flags } from "@oh-my-pi/pi-utils/cli";
 import { parseArgs } from "../cli/args";

packages/coding-agent/src/config/model-registry.ts

@@ -1,27 +1,19 @@
 import * as path from "node:path";
+import { registerCustomApi, unregisterCustomApis } from "@oh-my-pi/pi-ai/api-registry";
+import { readModelCache } from "@oh-my-pi/pi-ai/model-cache";
+import { createModelManager, type ModelManagerOptions, type ModelRefreshStrategy } from "@oh-my-pi/pi-ai/model-manager";
+import { enrichModelThinking } from "@oh-my-pi/pi-ai/model-thinking";
+import { getBundledModels, getBundledProviders } from "@oh-my-pi/pi-ai/models";
 import {
-	type Api,
-	type AssistantMessageEventStream,
-	type Context,
-	createModelManager,
-	enrichModelThinking,
-	getBundledModels,
-	getBundledProviders,
 	googleAntigravityModelManagerOptions,
 	googleGeminiCliModelManagerOptions,
-	type Model,
-	type ModelManagerOptions,
-	type ModelRefreshStrategy,
 	openaiCodexModelManagerOptions,
 	PROVIDER_DESCRIPTORS,
-	readModelCache,
-	registerCustomApi,
-	type SimpleStreamOptions,
-	type ThinkingConfig,
 	UNK_CONTEXT_WINDOW,
 	UNK_MAX_TOKENS,
-	unregisterCustomApis,
-} from "@oh-my-pi/pi-ai";
+} from "@oh-my-pi/pi-ai/provider-models";
+import type { Api, Context, Model, SimpleStreamOptions, ThinkingConfig } from "@oh-my-pi/pi-ai/types";
+import type { AssistantMessageEventStream } from "@oh-my-pi/pi-ai/utils/event-stream";
 
 // Sentinel for local-only OAuth token (LM Studio, vLLM) — declared inline to avoid loading
 // any provider module at startup. Must match `DEFAULT_LOCAL_TOKEN` in oauth/lm-studio.ts.