docs: ics29 middleware usage for app devs

[damiannolan]

Description

• About middleware application stacks
• How to configure an application stack composed of transfer and 29-fee
• How to configure an application stack composed of 27-interchain-accounts and 29-fee with associated auth module.

ref: #1408

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[charleenfei]

it's a little bit confusing that you mention app.go two sections above but only show the code snippet here -- maybe either move the sentence from above "For Cosmos SDK chains this setup...." down to the start of this section or move the code snippet up somewhere closer, and indicate that the code snippet is from app.go

[charleenfei]

also maybe mention a bit about the ordering of the middleware and how it will affect how the code is called (the bug from evmos)

-- this can also go into the main middleware docs but i dont think it hurts to repeat

[damiannolan]

Meant to leave a reply here earlier... I added an extra sentence to each example section reiterating the app/app.go direction. I feel the ordering is covered by the in line comments in the code snippets and should be covered in the middleware docs which are listed as {prereq} reading.

We may want to review the middleware developer/integration docs also to make sure they are up to date!

[charleenfei]

maybe be explicit somewhere about who these docs are for -- cosmos SDK devs

[seantking]

Clean. Nice work.

[charleenfei]

nice work!