fix: remove remaining 48 VantisOS/ duplicate files

[superninja-app]

Remove the last 48 files still under VantisOS/ prefix. All files already exist at root level — these are just duplicates left over from the migration in PR #81.

Files removed (all duplicates):

• VantisOS/examples/ (9 files) → already at examples/
• VantisOS/governance/ (12 files) → already at governance/
• VantisOS/monitoring/ (4 files) → already at monitoring/
• VantisOS/rfc/ (8 files) → already at rfc/
• VantisOS/security/ (6 files) → already at security/
• VantisOS/tools/ (2 files) → already at tools/
• VantisOS/well-known/ (1 file) → already at well-known/
• VantisOS/installer/, VantisOS/isolinux/, VantisOS/kernel/ (.gitkeep) → moved to root
• VantisOS/release/ (1 file) → moved to root

Result: Zero files under VantisOS/ prefix after this merge.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

---

VantisOS Team seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}