Expand Yomitan external profile tilde paths to home directory

- Normalize `yomitan.externalProfilePath` so `~` and `~/...` resolve to the current user home directory
- Add coverage for tilde expansion in integration config tests
- Update Yomitan config docs and tighten settings opener test assertion

src/config/resolve/integrations.ts

@@ -1,6 +1,19 @@
+import * as os from 'node:os';
+import * as path from 'node:path';
 import { ResolveContext } from './context';
 import { asBoolean, asNumber, asString, isObject } from './shared';
 
+function normalizeExternalProfilePath(value: string): string {
+  const trimmed = value.trim();
+  if (trimmed === '~') {
+    return os.homedir();
+  }
+  if (trimmed.startsWith('~/') || trimmed.startsWith('~\\')) {
+    return path.join(os.homedir(), trimmed.slice(2));
+  }
+  return trimmed;
+}
+
 export function applyIntegrationConfig(context: ResolveContext): void {
   const { src, resolved, warn } = context;
 
@@ -202,7 +215,7 @@ export function applyIntegrationConfig(context: ResolveContext): void {
   if (isObject(src.yomitan)) {
     const externalProfilePath = asString(src.yomitan.externalProfilePath);
     if (externalProfilePath !== undefined) {
-      resolved.yomitan.externalProfilePath = externalProfilePath.trim();
+      resolved.yomitan.externalProfilePath = normalizeExternalProfilePath(externalProfilePath);
     } else if (src.yomitan.externalProfilePath !== undefined) {
       warn(
         'yomitan.externalProfilePath',

src/config/resolve/jellyfin.test.ts

@@ -1,5 +1,6 @@
 import test from 'node:test';
 import assert from 'node:assert/strict';
+import * as os from 'node:os';
 import { createResolveContext } from './context';
 import { applyIntegrationConfig } from './integrations';
 
@@ -127,3 +128,16 @@ test('yomitan externalProfilePath is trimmed and invalid values warn', () => {
   assert.equal(invalid.context.resolved.yomitan.externalProfilePath, '');
   assert.ok(invalid.warnings.some((warning) => warning.path === 'yomitan.externalProfilePath'));
 });
+
+test('yomitan externalProfilePath expands leading tilde to the current home directory', () => {
+  const homeDir = os.homedir();
+  const { context } = createResolveContext({
+    yomitan: {
+      externalProfilePath: '~/.config/gsm_overlay',
+    },
+  });
+
+  applyIntegrationConfig(context);
+
+  assert.equal(context.resolved.yomitan.externalProfilePath, `${homeDir}/.config/gsm_overlay`);
+});