feat(codex): create and customize Codex config from /settings

Adds the Codex config panel (skills/agents/rules/memory/config editing,
mcp/plugins/marketplaces add-remove via the codex CLI) as the last piece
of parity with the Claude Code settings tab, plus the codex_config_changed
WebSocket type the client was missing, and docs for the new
/api/codex-config surface.

client/src/i18n/index.ts

@@ -83,6 +83,8 @@ import updates_en from "./locales/en/updates.json";
 import updates_vi from "./locales/vi/updates.json";
 import ccConfig_en from "./locales/en/ccConfig.json";
 import ccConfig_vi from "./locales/vi/ccConfig.json";
+import codexConfig_en from "./locales/en/codexConfig.json";
+import codexConfig_vi from "./locales/vi/codexConfig.json";
 import run_en from "./locales/en/run.json";
 import run_vi from "./locales/vi/run.json";
 import alerts_en from "./locales/en/alerts.json";
@@ -110,6 +112,7 @@ i18n
         errors: errors_en,
         updates: updates_en,
         ccConfig: ccConfig_en,
+        codexConfig: codexConfig_en,
         run: run_en,
         alerts: alerts_en,
         splash: splash_en,
@@ -128,6 +131,7 @@ i18n
         errors: errors_vi,
         updates: updates_vi,
         ccConfig: ccConfig_vi,
+        codexConfig: codexConfig_vi,
         run: run_vi,
         alerts: alerts_vi,
         splash: splash_vi,
@@ -150,6 +154,7 @@ i18n
       "errors",
       "updates",
       "ccConfig",
+      "codexConfig",
       "run",
       "alerts",
       "splash",