Fix help resolution and Win32 ownership soundness

[JamesLinYJ]

Summary

• replace legacy bare taskmgr.hlp / WinHelpW lookup with a fixed HTTPS project documentation target, explicit Shell/COM failure handling, and localized user feedback
• encode Win32 ownership with unsafe from_raw boundaries and RAII owners for handles, WTS memory, icons, interface tables, and copied SIDs
• make raw WM_NOTIFY, callback-buffer, crash, and secure-directory parsing contracts explicit, validated, and narrowly scoped
• remove caller-facing unsafe from ordinary process/network operations and keep FFI inside local unsafe blocks
• add focused tests for URL/error classification, UTF-16 truncation, raw directory record bounds, crash callback/path contracts, and typed ownership helpers

Root causes addressed

Issue #13 was caused by delegating a bare filename from an elevated UI to legacy WinHelp search behavior. The help target is now application-owned, deterministic, HTTPS-only, and independent of PATH or legacy file lookup.

Issue #14 was caused by safe APIs claiming ownership of arbitrary raw values or dereferencing caller-provided raw pointers, while unrelated operations were marked unsafe merely because their implementations used FFI. Raw ownership and pointer/message contracts are now represented by types where possible and by documented unsafe boundaries otherwise.

Validation

GitHub Actions CI run #7 passed on all supported architectures:

• x86_64: whitespace, rustfmt, all-target check, strict Clippy, tests, release build
• i686: all-target check, strict Clippy, tests, release build
• ARM64: all-target check, strict Clippy, release build
• all eight locale tables match all 283 TextKey variants
• legacy WinHelp and old safe ownership constructor symbols are absent

Fixes #13
Fixes #14