feat: remove PFM CIP from lemongrass

[evan-forbes]

Overview

Removes the PFM CIP from the lemongrass hardfork. This still needs discussion before merging

Checklist

• New and updated code has appropriate documentation
• New and updated code has new and/or updated testing
• Required CI checks are passing
• Visual proof for any user facing features like CLI or documentation updates
• Linked issues closed with keywords

[agouin]

Is there somewhere we can engage with the conversation on this? Not having PFM in Celestia will significantly impact rollup interoperability (e.g. TIA liquidity flow from rollups to rest of Cosmos eco)

[jackzampolin]

Also we've been in every core call and answered concerns about this for months. I'm interested to hear why and where this decision was made.

[evan-forbes]

Apologies for tossing up this issue without enough context

I'd like to put emphasis on the

This still needs discussion before merging

per the call

all CIPs that we didn't have audits are going through a more thorough review process

everyone is deeply grateful for all the work that has gone into this, its also important to note that no changes are needed for the CIP which is finalized.

The process for including new code is still an evolving process, and we just want to make sure that that process is followed. In the future, this process will be done before the meta CIP is created.

speaking only for myself here, if the formula being discussed in https://forum.celestia.org/t/criteria-for-cip-security-considerations/1625 is applied to the PFM, then even without an audit, its a highly desired feature that has been battle tested by important high value chains. We still need to go through the process of evaluating it ofc.

[evan-forbes]

see comment here

https://forum.celestia.org/t/cip-packet-forward-middleware/1359/11

personally, I'm leaning towards closing this PR. We still need to go through the proper process, but can reopen this PR if need be.