chore: bump version to v0.6.1 and exclude buggy apache-tvm-ffi releases (#2347)

## Summary

This PR bumps the FlashInfer version to v0.6.1 and updates the
apache-tvm-ffi dependency to exclude buggy releases.

## Changes

- Update `version.txt` to v0.6.1
- Add dependency exclusions for apache-tvm-ffi v0.1.8 and v0.1.8.post0
in both `requirements.txt` and `pyproject.toml`

Fixes #2346

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## Summary by CodeRabbit

## Release Notes

* **Chores**
  * Version bumped to 0.6.1
* Updated build and runtime dependencies to exclude problematic
apache-tvm-ffi versions (0.1.8 and 0.1.8.post0)

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Co-authored-by: claude[bot] <41898282+claude[bot]@users.noreply.github.com>
Co-authored-by: Zihao Ye <yzh119@users.noreply.github.com>

Author: yzh119

pyproject.toml

@@ -27,7 +27,7 @@ license-files = ["LICENSE", "LICENSE*.txt"]
 flashinfer = "flashinfer.__main__:cli"
 
 [build-system]
-requires = ["setuptools>=77", "packaging>=24", "apache-tvm-ffi>=0.1.6,<0.2"]
+requires = ["setuptools>=77", "packaging>=24", "apache-tvm-ffi>=0.1.6,!=0.1.8,!=0.1.8.post0,<0.2"]
 build-backend = "build_backend"
 backend-path = ["."]
 

requirements.txt

@@ -1,4 +1,4 @@
-apache-tvm-ffi>=0.1.6,<0.2
+apache-tvm-ffi>=0.1.6,!=0.1.8,!=0.1.8.post0,<0.2
 click
 einops
 ninja

version.txt

@@ -1 +1 @@
-0.6.0
+0.6.1