chore(types): fewer any casts; eslint warning ratchet 36 -> 29 (#210)

- Developer tools (send event, state event editor, room account data) and
  setMarkedUnread go through the typed helpers in utils/room and
  utils/accountData (new setRoomAccountData) instead of casting at the
  call site; sendStateEvent accepts a developer-chosen type string.
- SecretStorage passes the key description as the SDK's
  SecretStorageKeyDescription, CallEmbed replies with an IWidgetApiRequest,
  and fillMissingPowers writes through a Record instead of `as any`.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017PCb59uY3UKqDqt7B6hzd5

src/app/components/SecretStorage.tsx

@@ -1,6 +1,7 @@
 import React, { FormEventHandler, useCallback } from 'react';
 import { Box, Text, Button, Spinner, color } from 'folds';
 import { decodeRecoveryKey, deriveRecoveryKeyFromPassphrase } from 'matrix-js-sdk/lib/crypto-api';
+import type { SecretStorageKeyDescription } from 'matrix-js-sdk/lib/secret-storage';
 import { PasswordInput } from './password-input';
 import {
   SecretStorageKeyContent,
@@ -39,7 +40,10 @@ export function SecretStorageRecoveryPassphrase({
           bits,
         );
 
-        const match = await mx.secretStorage.checkKey(decodedRecoveryKey, keyContent as any);
+        const match = await mx.secretStorage.checkKey(
+          decodedRecoveryKey,
+          keyContent as SecretStorageKeyDescription,
+        );
 
         if (!match) {
           throw new Error('Invalid recovery passphrase.');
@@ -132,7 +136,10 @@ export function SecretStorageRecoveryKey({
       async (recoveryKey) => {
         const decodedRecoveryKey = decodeRecoveryKey(recoveryKey);
 
-        const match = await mx.secretStorage.checkKey(decodedRecoveryKey, keyContent as any);
+        const match = await mx.secretStorage.checkKey(
+          decodedRecoveryKey,
+          keyContent as SecretStorageKeyDescription,
+        );
 
         if (!match) {
           throw new Error('Invalid recovery key.');