fix: pre-existing test failures across 15+ packages in CI

[CodeMonkeyCybersecurity]

Summary

After fixing CGO compilation in CI (#74), many pre-existing test failures are now visible that were previously masked by build failures. These need to be fixed package by package.

Failing Packages (ci-unit)

Package	Test	Root Cause
pkg/backup	TestSaveConfig/save_invalid_config	Expects validation error, gets mkdir /etc/eos: permission denied (CI has no /etc/eos)
pkg/btrfs	TestCreateSubvolume_ErrorPaths	Error message mismatch: gets "device path cannot be empty" but expects "parent path does not exist"
pkg/btrfs	TestDeviceHasFilesystem_Mock	Expected false, actual true
pkg/btrfs	TestCreateSnapshot_Validation	Error message mismatch
pkg/cephfs	FuzzConfigStructValidation/seed#2	Negative MON count (-1), dangerous device path not rejected
pkg/clean	TestSanitizeName_EdgeCases	Long filename and tabs/newlines handling
pkg/clean	TestPathOperations	current_directory and Windows_path cases
pkg/cloudinit	TestGeneratorValidateConfig_Comprehensive	hostname_too_long, invalid_hostname_characters, empty_username
pkg/container	Various	37s runtime, likely timeout or Docker dependency
pkg/crypto	Various	51s runtime
pkg/crypto/pq	Various	Post-quantum crypto tests
pkg/database_management	Various	Database dependency
pkg/docker	Various	Docker dependency
pkg/eos_err	Various	Error handling tests
pkg/eos_io	Various	IO tests
pkg/eos_postgres	Various	Postgres dependency

Failing Packages (ci-integration)

Package	Test	Root Cause
pkg/vault	TestSecureRootTokenFallback	Calls PromptSecret in CI (no TTY), panics on nil reader after 900s timeout

Categories

1. Error message mismatches (btrfs, clean, cloudinit): Tests assert specific error strings that changed. Fix by updating assertions.
2. CI environment dependencies (backup, container, docker, postgres): Tests need root/Docker/Postgres. Fix with t.Skip guards or CI service containers.
3. TTY-dependent tests (vault): Tests call interactive prompts. Fix with t.Skip when os.Stdin is not a terminal.
4. Validation gaps (cephfs): Fuzz tests finding real input validation issues. Fix the validators.
5. Long-running tests (container, crypto): May need -timeout increase or -short skip.

Priority

P2 - These don't affect production code, only CI reliability.

Related

• fix(ci): install librados-dev in CI runners for CGO compilation #74 (CGO deps in CI - FIXED)
• chore: Makefile test-e2e-full uses sudo which causes root-owned files #70 (sudo test root-owned files)