feat: add hashline editing and TypeScript LSP

extensions/lsp-config.ts

@@ -0,0 +1,49 @@
+import { mkdirSync, readFileSync, renameSync, writeFileSync } from "node:fs";
+import { dirname, join } from "node:path";
+import { fileURLToPath } from "node:url";
+
+const BUNDLE_CONFIG_PATH = fileURLToPath(new URL("../config/lsp.json", import.meta.url));
+const TYPESCRIPT_SERVER_ID = "typescript-language-server";
+
+interface LspConfigFile {
+	version?: number;
+	servers?: Array<{
+		id?: string;
+		bin?: string;
+		args?: string[];
+		[key: string]: unknown;
+	}>;
+}
+
+export interface TypeScriptLspRuntime {
+	nodeBinary: string;
+	serverCliPath: string;
+}
+
+export function materializeBundleLspConfig(source: string, runtime: TypeScriptLspRuntime): string {
+	const config = JSON.parse(source) as LspConfigFile;
+	const server = config.servers?.find((entry) => entry.id === TYPESCRIPT_SERVER_ID);
+	if (server === undefined) {
+		throw new Error(`Missing ${TYPESCRIPT_SERVER_ID} entry in bundled LSP config`);
+	}
+
+	server.bin = runtime.nodeBinary;
+	server.args = [runtime.serverCliPath, "--stdio"];
+	return `${JSON.stringify(config, null, 2)}\n`;
+}
+
+export function deployBundleLspConfig(agentDir: string, runtime: TypeScriptLspRuntime): void {
+	const targetPath = join(agentDir, "lsp.json");
+	const bundledConfig = materializeBundleLspConfig(readFileSync(BUNDLE_CONFIG_PATH, "utf8"), runtime);
+
+	try {
+		if (readFileSync(targetPath, "utf8") === bundledConfig) return;
+	} catch {
+		// Missing or unreadable target: replace it with the bundle-owned baseline.
+	}
+
+	mkdirSync(dirname(targetPath), { recursive: true });
+	const temporaryPath = `${targetPath}.my-pi.tmp`;
+	writeFileSync(temporaryPath, bundledConfig, "utf8");
+	renameSync(temporaryPath, targetPath);
+}