feat(core): use gemini-2.5-pro as default advanced model

[parse]

The Gemini provider used gemini-2.5-flash for both fast and advanced
tiers, unlike OpenAI and Anthropic which use stronger models for the
analysis stage. Switch the advanced default to gemini-2.5-pro for
better drift analysis quality.

Also consolidate model defaults in config.ts by importing from each
provider's models.ts, eliminating duplicate hardcoded strings.

Summary by CodeRabbit

Release Notes

• Chores

  • Updated the default Gemini advanced model configuration from Flash to Pro across all system configuration files, schema definitions, and configuration settings throughout the platform.

• Documentation

  • Updated user documentation, guides, and reference materials to reflect the new Gemini Pro model as the default advanced selection option for Gemini provider integration.

[coderabbitai]

Caution

Review failed

The pull request is closed.

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 97138dec-f3e1-49ab-9528-e0623366bf05

📥 Commits

Reviewing files that changed from the base of the PR and between ee831c6 and 751c7c7.

📒 Files selected for processing (7)

• .env.example
• packages/core/schemas/eroderc.schema.json
• packages/core/src/providers/gemini/models.ts
• packages/core/src/utils/config.ts
• packages/web/public/schemas/v0/eroderc.schema.json
• packages/web/src/content/docs/docs/how-it-works.md
• packages/web/src/content/docs/docs/reference/ai-providers.md

---

📝 Walkthrough

Walkthrough

This PR updates the default advanced Gemini model from gemini-2.5-flash to gemini-2.5-pro across configuration schemas, code constants, and documentation. Additionally, hardcoded model strings in the config utility are refactored to use imported model constants for maintainability.

Changes

Cohort / File(s)	Summary
Gemini Advanced Model Update packages/core/schemas/eroderc.schema.json, packages/core/src/providers/gemini/models.ts, packages/web/public/schemas/v0/eroderc.schema.json	Default value for Gemini advancedModel changed from gemini-2.5-flash to gemini-2.5-pro across schema definitions and model constants.
Config Constants Refactor packages/core/src/utils/config.ts	Imported model constants (ANTHROPIC_MODELS, GEMINI_MODELS, OPENAI_MODELS) and replaced hardcoded model strings with constant references in ConfigSchema defaults for all three providers (fast and advanced tiers).
Configuration & Documentation .env.example, packages/web/src/content/docs/docs/how-it-works.md, packages/web/src/content/docs/docs/reference/ai-providers.md	Updated environment example comment, documentation references, and API provider docs to reflect Gemini Pro as the default advanced model instead of Flash.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Poem

🐰 A flash becomes a pro today,
Constants replace the hardcoded way,
Through schemas, docs, and configs bright,
The Gemini model takes its flight! ✨

✨ Finishing Touches

• 📝 Generate docstrings (stacked PR)
• 📝 Generate docstrings (commit on current branch)

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch claude/update-gemini-default-model-omAFB

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}