mito-ai: add support for gpt-5.5

[aarondr77]

Description

gpt 5.5!

Documentation

Note if any new documentation needs to addressed or reviewed.

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Note

Medium Risk
Moderate risk because it changes the default/available model lists and ordering used for model selection across CLI, core utilities, and UI, which could affect which model is chosen in enterprise/router scenarios.

Overview
Adds gpt-5.5 as a first-class supported model across the stack: core STANDARD_MODELS/OPENAI_MODEL_ORDER, CLI name resolution (including aliasing gpt 5.5 -> gpt-5.5), and the frontend model selector (display constants, metadata, and tests).

Also introduces get_smartest_model_for_selected_model in model_utils (and a placeholder test suite), and updates UI/test fixtures to include claude-sonnet-4-6 in the model list (while keeping it commented out of Anthropic ordering/standard models).

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Project	Deployment	Actions	Updated (UTC)
monorepo	Ready	Preview, Comment	Apr 24, 2026 7:56pm

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

There are 2 total unresolved issues (including 1 from previous review).

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