Refresh Avian provider: add DeepSeek, GLM, MiniMax and Kimi pricing

[ayaangazali]

Avian's lineup changed completely since avian.yml was last touched. Their pricing page (https://avian.io/pricing/) now lists DeepSeek V4 Flash/Pro, DeepSeek V3.2, GLM-5, GLM-5.1, MiniMax M2.5 and Kimi K2.5/K2.6, each with a cache price. The four Meta Llama entries no longer appear there, so I marked them deprecated rather than deleting them.

Closes #322

Two judgment calls worth a sanity check:

• the pricing table's column is labeled just "Cache", I mapped it to cache_read_mtok
• model ids follow Avian's documented request format (their site shows model="DeepSeek-V3.2" in the code example); only V3.2 appears verbatim, the others follow the same hyphenated pattern

Gates: make build / lint / typecheck / test all green (coverage stays 100%), npm run ci green, pre-commit all-files green.

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quick note: I'm a college freshman getting into OSS. I put this together with Claude Code helping me along and checked every number against the pricing page myself. happy to fix anything that looks off :)

[Copilot]

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[cubic-dev-ai]

All reported issues were addressed across 6 files

Not reviewed (too large): prices/data_slim.json (~2 lines), prices/data.json (~2 lines) - if these are generated or fixture files, add them to ignored paths to exclude them from future reviews.

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[ayaangazali]

good catch from cubic on the model ids. avian's docs (https://avian.io/docs/ and https://avian.io/models/) do use provider-prefixed ids like deepseek/deepseek-v3.2 and moonshotai/kimi-k2.6, the unprefixed form only shows up in their homepage snippet. switched the canonical ids to the prefixed forms and kept the unprefixed ones as match aliases in 1ed44da. all gates re-run green.

[ayaangazali]

@cubic-dev-ai looks like the review run on the latest commit (1ed44da) errored out rather than finding anything, could you take another pass?

[cubic-dev-ai]

@cubic-dev-ai looks like the review run on the latest commit (1ed44da) errored out rather than finding anything, could you take another pass?

@ayaangazali I have started the AI code review. It will take a few minutes to complete.

[cubic-dev-ai]

No issues found across 6 files

Not reviewed (too large): prices/data_slim.json (~2 lines), prices/data.json (~2 lines) - if these are generated or fixture files, add them to ignored paths to exclude them from future reviews.

_{Re-trigger cubic}

[Kludex]

Superseded by #610, rebuilt from current main with Avian's current catalog and public Python and JavaScript pricing tests. Thank you for the original implementation and the model ID research.