Drop files on Explorer tabs as Explorer would, without the interop DLLs

[leafOfTree]

Summary

Dropping files on tabs

• No interop DLLs. Explorer folders are found late bound through Shell.Application, so Interop.SHDocVw.dll and Interop.Shell32.dll are gone from the repo and the build.
• Behaves like Explorer. Dropping on a File Explorer tab moves within one drive and copies across drives. Ctrl copies, Shift moves, and files dropped back on their own folder's tab stay put. Right-drag offers the menu again, now in the app's theme.
• One shell operation, on its own thread. All files go together: one progress dialog, one round of name conflicts, one Ctrl+Z in Explorer to undo, and the tabs stay responsive.
• A line under the strip says what a drop does, such as "Move to Downloads", in the app's theme. The source's drag image is not shown, as it covered the tabs being aimed at. A tab's window comes forward only once the pointer has rested on it for 300 ms.
• Names outside the code page. Dropped paths are read through DragQueryFileW. The ANSI entry point turned a name such as 小麦-0.1.24-x64-setup.exe into question marks, so the drop did nothing.
• Windows 11 Explorer tabs. A drop goes to the folder on show, not the first tab's folder.
• Explorer refreshes. Open Explorer windows refresh the folders a drop touched.
• The folder's window keeps the foreground after the progress dialog closes, unless you have moved on to another window.
• Robustness:
  • Windows are matched by handle before their view is read, so an Explorer view without a folder no longer breaks every drop.
  • The folder is looked up once per hovered tab.
  • Long dropped paths are read in full, and each drop's data is freed.

Other

• Full titles on hover. Resting on a tab whose title is cut short shows the whole title under the strip, in the app's theme. Title tips stay off open menus.
• Crash log link. It is offered only when the log holds a crash, and sits apart at the right of the Support links.
• README. Explains dropping files on tabs, and that Windows blocks drags into apps running as administrator.

Notes

• Rebased onto current master. The earlier "Put Taskbar before Window switcher" commit was already merged through Combined taskbar icons: apply to open groups, badge and preview fixes #54 and dropped out. The README conflict was resolved in the new, shorter README style.

Tests

• tests/Run-Tests.ps1: all suites pass locally after the rebase. The branch adds checks in Architecture, Reliability and TabInteraction, including reading a dropped path with Chinese characters and moving that file. That check fails without the fix.
• The Release build (single static exe) and the smoke test run in CI. Locally the Release output was locked by a running WindowTabs.