feat: add search API key configuration

extensions/search-config.ts

@@ -0,0 +1,57 @@
+import { readFileSync } from "node:fs";
+import { homedir } from "node:os";
+import { join } from "node:path";
+
+export const SEARCH_API_KEY_NAMES = ["TAVILY_API_KEY", "EXA_API_KEY", "KEENABLE_API_KEY"] as const;
+
+type SearchApiKeyName = (typeof SEARCH_API_KEY_NAMES)[number];
+type SearchEnvironment = Record<string, string | undefined>;
+
+const SAFE_VALUE = /^[A-Za-z0-9._-]+$/;
+
+export function getSearchConfigPath(env: SearchEnvironment = process.env): string {
+	if (env.MY_PI_SEARCH_CONFIG?.trim()) {
+		return env.MY_PI_SEARCH_CONFIG.trim();
+	}
+	const configHome = env.XDG_CONFIG_HOME?.trim() || join(env.HOME?.trim() || homedir(), ".config");
+	return join(configHome, "my-pi", "search.env");
+}
+
+export function parseSearchConfig(text: string): Partial<Record<SearchApiKeyName, string>> {
+	const parsed: Partial<Record<SearchApiKeyName, string>> = {};
+	for (const rawLine of text.split(/\r?\n/u)) {
+		const line = rawLine.trim().replace(/^export[ \t]+/u, "");
+		if (!line || line.startsWith("#")) continue;
+		const separator = line.indexOf("=");
+		if (separator < 1) continue;
+		const name = line.slice(0, separator).trim() as SearchApiKeyName;
+		const value = line.slice(separator + 1).trim();
+		if (!SEARCH_API_KEY_NAMES.includes(name) || !SAFE_VALUE.test(value)) continue;
+		parsed[name] = value;
+	}
+	return parsed;
+}
+
+/** Load package-managed search credentials without overriding explicit process environment values. */
+export function loadSearchConfigEnv(
+	env: SearchEnvironment = process.env,
+	configPath = getSearchConfigPath(env),
+): Partial<Record<SearchApiKeyName, string>> {
+	let parsed: Partial<Record<SearchApiKeyName, string>> = {};
+	try {
+		parsed = parseSearchConfig(readFileSync(configPath, "utf8"));
+	} catch {
+		// Missing or unreadable config is equivalent to an empty package-managed config.
+	}
+	const effective: Partial<Record<SearchApiKeyName, string>> = {};
+	for (const name of SEARCH_API_KEY_NAMES) {
+		if (!env[name]?.trim() && parsed[name]) env[name] = parsed[name];
+		if (env[name]?.trim()) effective[name] = env[name]?.trim();
+	}
+	return effective;
+}
+
+/** Load search API keys before provider extensions initialize. */
+export default function searchConfigExtension(): void {
+	loadSearchConfigEnv();
+}