[jimfangx]

Depends on: firesim/firesim#1904
Then need to rewrite submodule reference before merging this.

Conda is really slow, move to Pixi, keeping chipyard installs in 15-20 mins depending on system.

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Type of change:

• Bug fix
• New feature
• Other enhancement

Impact:

• RTL change
• Software change (RISC-V software)
• Build system change
• Other

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