feat(io): add initial O_DIRECT write support with dynamic alignment a…

[NikhilAdhau]

…nd truncation

• Introduce first-time support for O_DIRECT file writes
• Dynamically detect sector size to ensure proper buffer alignment
• Ensure all O_DIRECT writes use aligned buffers for compatibility
• Truncate files post-write to match actual data size and remove padding
• Add tests covering O_DIRECT behavior (padding, empty writes, etc.)
• Add configuration and YAML flags to enable/disable O_DIRECT

Changes

Fixes

Tests

Tasks to complete before merging PR:

• Ensure system tests are passing. If not Run them manually to check for any regressions 📋
• Do any new system tests need added to test this change? do any existing system tests need updated? If so create a PR at 0chain/system_test
• Merge your system tests PR to master AFTER merging this PR

Associated PRs (Link as appropriate):

• 0chain:
• gosdk:
• system_test:
• zboxcli:
• zwalletcli:
• Other: ...