fix(shared): drop .js extensions from relative imports for Metro

packages/shared/src/index.ts and all sub-modules used .js extensions on
relative imports (e.g. './admin/index.js') pointing at .ts source files.
TypeScript with moduleResolution: "Bundler" doesn't need them, and
Metro's eager exporter (used for preview / production builds) reads
them literally and fails — only the dev-server Metro fell back to .ts.

Workspace typecheck remains 8/8 green; Vite and TS Bundler resolution
already accept both styles, so desktop is unaffected.

packages/shared/src/auth/device.ts

@@ -1,8 +1,8 @@
-import { fromBase64, generateX25519KeyPair, toBase64, wipe } from '../crypto/index.js';
-import { bytesToPgHex, pgHexToBytes } from '../supabase/bytea.js';
-import type { AppSupabaseClient } from '../supabase/client.js';
-import type { DevicePlatform } from '../supabase/types.js';
-import type { SecretStore } from './secure-storage.js';
+import { fromBase64, generateX25519KeyPair, toBase64, wipe } from '../crypto/index';
+import { bytesToPgHex, pgHexToBytes } from '../supabase/bytea';
+import type { AppSupabaseClient } from '../supabase/client';
+import type { DevicePlatform } from '../supabase/types';
+import type { SecretStore } from './secure-storage';
 
 export interface RegisterDeviceParams {
   name: string;          // user-facing, e.g. "Dennis Laptop"
@@ -153,7 +153,7 @@ export async function saveDevicePrivateKey(
 }
 
 // Restores a device record from a backup by re-seeding the local private key
-// store for an EXISTING server-side device row. Does NOT insert a new row —
+// store for an EXISTING server-side device row. Does NOT insert a new row —
 // the original row is kept intact so conversation-key bundles stay valid.
 // Throws when the server-side device was removed (the backup is then unusable;
 // user must provision a fresh device and get conv-keys shared from another
@@ -169,7 +169,7 @@ export async function restoreDeviceFromServerRecord(params: {
   if (!session.user) throw new Error('not authenticated');
   if (session.user.id !== params.userId) {
     throw new Error(
-      'Backup is for a different account — sign in as the owner before restoring.',
+      'Backup is for a different account — sign in as the owner before restoring.',
     );
   }
 
@@ -182,7 +182,7 @@ export async function restoreDeviceFromServerRecord(params: {
   if (error) throw error;
   if (!row) {
     throw new Error(
-      'Device record not found on server — it was removed. Backup is no longer valid; register a new device instead.',
+      'Device record not found on server — it was removed. Backup is no longer valid; register a new device instead.',
     );
   }
 
@@ -211,5 +211,5 @@ export function deviceIdStorageKey(userId: string): string {
 }
 
 // Intentional re-exports so app layers only need @chat-app/shared/auth.
-export type { SecretStore } from './secure-storage.js';
+export type { SecretStore } from './secure-storage';
 export { toBase64 as base64FromBytes, fromBase64 as bytesFromBase64 };

packages/shared/src/auth/index.ts

@@ -1,3 +1,3 @@
-export * from './device.js';
-export * from './magic-link.js';
-export * from './profile.js';
+export * from './device';
+export * from './magic-link';
+export * from './profile';

packages/shared/src/auth/magic-link.ts

@@ -1,5 +1,5 @@
-import type { SupportedLocale } from '../i18n/types.js';
-import type { AppSupabaseClient } from '../supabase/client.js';
+import type { SupportedLocale } from '../i18n/types';
+import type { AppSupabaseClient } from '../supabase/client';
 
 export interface SignupParams {
   email: string;
@@ -58,7 +58,7 @@ export async function loginWithMagicLink(
 }
 
 // Parse a callback URL produced by the magic-link email and establish a session.
-// Works for both PKCE (`?code=…`) and legacy token-hash (`#access_token=…`).
+// Works for both PKCE (`?code=…`) and legacy token-hash (`#access_token=…`).
 export async function completeSessionFromUrl(
   client: AppSupabaseClient,
   url: string,
@@ -91,14 +91,14 @@ export async function completeSessionFromUrl(
 export async function signOut(client: AppSupabaseClient): Promise<void> {
   // `scope: 'local'` only ends the session in THIS client. Without it Supabase
   // defaults to 'global', which invalidates the user's refresh tokens
-  // everywhere — meaning a logout in the browser would also kick the desktop
+  // everywhere — meaning a logout in the browser would also kick the desktop
   // app (and vice versa) the next time it tries to refresh its token.
   const { error } = await client.auth.signOut({ scope: 'local' });
   if (error) throw error;
 }
 
 // Verify a 6-digit OTP that arrived via magic-link email. Establishes a
-// session in the CURRENT webview — no browser redirect involved. Used by the
+// session in the CURRENT webview — no browser redirect involved. Used by the
 // desktop/mobile apps where cross-origin redirects don't carry the session
 // back to the native webview.
 export async function verifyMagicLinkOtp(

packages/shared/src/auth/profile.ts

@@ -1,6 +1,6 @@
-import type { SupportedLocale } from '../i18n/types.js';
-import type { AppSupabaseClient } from '../supabase/client.js';
-import type { Database, PresenceState } from '../supabase/types.js';
+import type { SupportedLocale } from '../i18n/types';
+import type { AppSupabaseClient } from '../supabase/client';
+import type { Database, PresenceState } from '../supabase/types';
 
 type ProfileUpdate = Database['public']['Tables']['profiles']['Update'];
 
@@ -75,7 +75,7 @@ export async function getProfileByUsername(
   const { data, error } = await client
     .from('profiles')
     .select(PROFILE_COLS)
-    // citext column compares CI server-side — send raw input, don't force case.
+    // citext column compares CI server-side — send raw input, don't force case.
     .eq('username', username.trim())
     .maybeSingle();
   if (error) throw error;
@@ -89,7 +89,7 @@ export async function isUsernameAvailable(
   const { count, error } = await client
     .from('profiles')
     .select('user_id', { count: 'exact', head: true })
-    // citext compares CI — no manual normalization needed.
+    // citext compares CI — no manual normalization needed.
     .eq('username', username.trim());
   if (error) throw error;
   return (count ?? 0) === 0;