v3 refactor

[fnerdman]

This is the minimal amount of changes needed to enable v3 refactor.
The manifest layers have their respective v3 branches setup as well. These need to be merged for this PR to work.
To test the changes one can manually edit the manifest:

repo init -u https://github.com/flashbots/yocto-manifests.git -b v3 -m tdx-rbuilder.xml
sed -i 's/main/v3/g' .repo/manifests/tdx-rbuilder.xml
repo sync
source setup

[fnerdman]

Dependent PRs:
flashbots/meta-confidential-compute#42
flashbots/meta-confidential-compute#38
flashbots/meta-searcher#15
flashbots/meta-evm#57
flashbots/meta-observability#19
flashbots/meta-custom-podman#3

[Ruteri]

What I'd propose to do in order to get this merged is as follows:

• Separately merge each dependent PR that we can without breaking changes
• The changes left will not have any version bumps — only refactoring, which will be much simpler to test (basically if the binaries are as expected it should work)
• Wait until v1.2 is in production
• Merge the remaining dependent PRs together with this PR, and thoroughly test as a part of v1.3 release