feat: gemma 3

[sozercan]

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[Copilot]

Pull Request Overview

This PR upgrades the supported Gemma model from version 2 (2B parameters) to version 3 (4B parameters) across all documentation and configuration files. It also adds some cosmetic improvements like emojis for certain models and fixes table formatting.

• Replaces Gemma 2 with Gemma 3 in main model tables
• Updates model parsing scripts to include the new model identifier
• Adds new Gemma 3 configuration file and removes old Gemma 2 config
• Updates CI/CD workflows to build Gemma 3 instead of Gemma 2

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
website/docs/premade-models.md	Updates main model tables to replace Gemma 2 with Gemma 3, adds Gemma 2 to legacy section, fixes table formatting
scripts/parse-models.sh	Updates model list to include gemma-3-4b-instruct instead of gemma-2-2b-instruct
models/gemma-3-4b-instruct.yaml	Adds new configuration file for Gemma 3 model with proper GGUF source and template settings
models/gemma-2-2b-instruct.yaml	Removes old Gemma 2 configuration file
README.md	Updates README model tables to reflect Gemma 3 replacement
.github/workflows/update-models.yaml	Updates CI workflow default models list to build Gemma 3 instead of Gemma 2