feat(settings): add Hermes config dir override with data-driven dispatch

Adds a dedicated Hermes row to the directory-override settings so users
can point CC Switch at alternate Hermes config locations (e.g. a second
profile directory for work/personal split). `get_config_dir` on the
Rust side already supports hermes; this just wires up the frontend row.

Wiring it through `useDirectorySettings` revealed a scaling problem:
every supported app required five parallel ternary chains across
`computeDefaultConfigDir`, `updateDirectory`, `browseDirectory`,
`resetDirectory`, and `updateDirectoryState`. Replaces those with two
lookup tables (`APP_DIRECTORY_META`, `DIRECTORY_KEY_TO_SETTINGS_FIELD`)
so adding the next app is two entries, not fifteen edit sites.

Drive-by cleanup from the same touch:
* `resetAllDirectories` takes a `ResolvedAppDirectoryOverrides` object
  instead of five positional optional strings.
* `setResolvedDirs` returns the same reference when the sanitized
  value is unchanged, so no-op edits don't cascade renders.

Also lands all i18n updates for this series (`hermesConfigDir` and
placeholder, Memory section's enable/disable/toggleFailed copy, and
the reworded `schemaMigratedV12` warning) in zh/en/ja together.

src/components/settings/SettingsPage.tsx

@@ -317,6 +317,7 @@ export function SettingsPage({
                             geminiDir={settings.geminiConfigDir}
                             opencodeDir={settings.opencodeConfigDir}
                             openclawDir={settings.openclawConfigDir}
+                            hermesDir={settings.hermesConfigDir}
                             onDirectoryChange={updateDirectory}
                             onBrowseDirectory={browseDirectory}
                             onResetDirectory={resetDirectory}