Restructure src/ modules with consistent internal organization

Reorganize major src/ directories to follow a consistent pattern with
core/, menu/, submenu/, inputs/, logs/, layout/, feedback/ subdirectories.

Changes by module:

- stores/: Move 5 store files to stores/core/
- utils/: Create core/ (terminal, tools, etc.) and menu/ (progress-bar)
- api/: Create copilot/core/, copilot/auth/, ollama/core/
- providers/: Create core/, copilot/core/, copilot/auth/, ollama/core/, login/core/
- ui/: Create core/, banner/core/, banner/menu/, spinner/core/,
       input-editor/core/, components/core/, components/menu/
- tools/: Create core/ for registry.ts and types.ts
- tui-solid/: Reorganize components/ into menu/, submenu/, inputs/,
              logs/, modals/, panels/, layout/, feedback/
- commands/: Create core/ for runner.ts and handlers.ts
- services/: Create core/ for agent.ts, permissions.ts, session.ts,
             executor.ts, config.ts

All imports updated to use new paths. TypeScript compilation verified.

src/index.ts

@@ -1,7 +1,7 @@
 #!/usr/bin/env node
 
 import { Command } from "commander";
-import { handleCommand } from "@commands/handlers";
+import { handleCommand } from "@commands/core/handlers";
 import { execute } from "@commands/chat-tui";
 import versionData from "@/version.json";
 import {
@@ -10,14 +10,14 @@ import {
   getProviderNames,
   displayProvidersStatus,
 } from "@providers/index";
-import { getConfig } from "@services/config";
-import { deleteSession, getSessionSummaries } from "@services/session";
+import { getConfig } from "@services/core/config";
+import { deleteSession, getSessionSummaries } from "@services/core/session";
 import {
   initializePermissions,
   listPatterns,
   addGlobalPattern,
   addLocalPattern,
-} from "@services/permissions";
+} from "@services/core/permissions";
 import {
   projectConfig,
   initProject,
@@ -32,7 +32,7 @@ import {
   buildLearningsContext,
 } from "@services/project-config";
 import { createPlan, displayPlan, approvePlan } from "@services/planner";
-import { ensureXdgDirectories } from "@utils/ensure-directories";
+import { ensureXdgDirectories } from "@utils/core/ensure-directories";
 import chalk from "chalk";
 
 // Read version from version.json