feat: add Claude Opus 4.6 to built-in model catalog (#9853)

* feat: add Claude Opus 4.6 to built-in model catalog

- Update default model from claude-opus-4-5 to claude-opus-4-6
- Add opus-4.6 model ID normalization
- Add claude-opus-4-6 to live model filter prefixes
- Update image tool to prefer claude-opus-4-6 for vision
- Add CLI backend alias for opus-4.6
- Update onboard auth default selections to include opus-4.6
- Update model picker placeholder

Closes #9811

* test: update tests for claude-opus-4-6 default

- Fix model-alias-defaults test to use claude-opus-4-6
- Fix image-tool test to expect claude-opus-4-6 in fallbacks

* feat: support claude-opus-4-6

* docs: update changelog for opus 4.6 (#9853) (thanks @TinyTb)

* chore: bump pi to 0.52.0

---------

Co-authored-by: Slurpy <slurpy@openclaw.ai>
Co-authored-by: Peter Steinberger <steipete@gmail.com>

src/agents/cli-backends.ts

@@ -9,8 +9,10 @@ export type ResolvedCliBackend = {
 
 const CLAUDE_MODEL_ALIASES: Record<string, string> = {
   opus: "opus",
+  "opus-4.6": "opus",
   "opus-4.5": "opus",
   "opus-4": "opus",
+  "claude-opus-4-6": "opus",
   "claude-opus-4-5": "opus",
   "claude-opus-4": "opus",
   sonnet: "sonnet",