JSON-mode with schema following, new models

What's Changed

• Fix url by @jsntn in #118
• Add Gemini 2.0 flash to the list of Gemini models by @ahyatt in #121
• Add llama-3.3 and QwQ models by @ahyatt in #122
• Add ability to get JSON object as a specific schema by @ahyatt in #123
• Add Snowflake Artic Embed 2.0 model by @s-kostyaev in #125
• docs: update README.org by @eltociear in #126
• Add gemini-2.0-flash-thinking-exp, fix output selection by @ahyatt in #127
• Fix missing capabilities in Gemini thinking model by @ahyatt in #128
• Fix integration test false positives by @ahyatt in #129

New Contributors

• @jsntn made their first contribution in #118
• @eltociear made their first contribution in #126

Full Changelog: 0.19.1...0.20.0