feat(coding-agent): ResourceLoader, package management, and /reload command (#645)

- Add ResourceLoader interface and DefaultResourceLoader implementation
- Add PackageManager for npm/git extension sources with install/remove/update
- Add session.reload() and session.bindExtensions() APIs
- Add /reload command in interactive mode
- Add CLI flags: --skill, --theme, --prompt-template, --no-themes, --no-prompt-templates
- Add pi install/remove/update commands for extension management
- Refactor settings.json to use arrays for skills, prompts, themes
- Remove legacy SkillsSettings source flags and filters
- Update SDK examples and documentation for ResourceLoader pattern
- Add theme registration and loadThemeFromPath for dynamic themes
- Add getShellEnv to include bin dir in PATH for bash commands

packages/coding-agent/examples/sdk/07-context-files.ts

@@ -4,33 +4,36 @@
  * Context files provide project-specific instructions loaded into the system prompt.
  */
 
-import { createAgentSession, discoverContextFiles, SessionManager } from "@mariozechner/pi-coding-agent";
+import { createAgentSession, DefaultResourceLoader, SessionManager } from "@mariozechner/pi-coding-agent";
 
-// Discover AGENTS.md files walking up from cwd
-const discovered = discoverContextFiles();
-console.log("Discovered context files:");
-for (const file of discovered) {
-	console.log(`  - ${file.path} (${file.content.length} chars)`);
-}
-
-// Use custom context files
-await createAgentSession({
-	contextFiles: [
-		...discovered,
-		{
-			path: "/virtual/AGENTS.md",
-			content: `# Project Guidelines
+const loader = new DefaultResourceLoader({
+	agentsFilesOverride: (current) => ({
+		agentsFiles: [
+			...current.agentsFiles,
+			{
+				path: "/virtual/AGENTS.md",
+				content: `# Project Guidelines
 
 ## Code Style
 - Use TypeScript strict mode
 - No any types
 - Prefer const over let`,
-		},
-	],
+			},
+		],
+	}),
+});
+await loader.reload();
+
+// Discover AGENTS.md files walking up from cwd
+const discovered = loader.getAgentsFiles().agentsFiles;
+console.log("Discovered context files:");
+for (const file of discovered) {
+	console.log(`  - ${file.path} (${file.content.length} chars)`);
+}
+
+await createAgentSession({
+	resourceLoader: loader,
 	sessionManager: SessionManager.inMemory(),
 });
 
 console.log(`Session created with ${discovered.length + 1} context files`);
-
-// Disable context files:
-// contextFiles: []