fix: update Claude usage window to support 4.6 models

The usage progress bar only matched claude-sonnet-4-5 and
claude-opus-4-5-thinking. After upgrading to 4.6, the backend returns
claude-sonnet-4-6/claude-opus-4-6-thinking which didn't match,
causing the Claude usage bar to not display.

- Add claude-sonnet-4-6 and claude-opus-4-6-thinking to the match list
- Rename label from "C4.5" to "Claude" for future-proofing

frontend/src/i18n/locales/en.ts

@@ -2047,7 +2047,7 @@ export default {
         gemini3Pro: 'G3P',
         gemini3Flash: 'G3F',
         gemini3Image: 'G3I',
-        claude45: 'C4.5'
+        claude: 'Claude'
       },
       tier: {
         free: 'Free',

frontend/src/i18n/locales/zh.ts

@@ -1583,7 +1583,7 @@ export default {
         gemini3Pro: 'G3P',
         gemini3Flash: 'G3F',
         gemini3Image: 'G3I',
-        claude45: 'C4.5'
+        claude: 'Claude'
       },
       tier: {
         free: 'Free',