Integrate native Rime and stabilize input, output, and rendering

- Add optional modifier-only Super binding whose tap is cancelled by
  other input, focus changes, grabs, locks, and session teardown.
- Ship the native ferese-rime user service, Rime defaults, installer
  inventory, package dependencies, session environment, and docs.
- Vendor Smithay 8a27023 with the SHM texture-cache format fix and add
  GPU regressions for format changes and resize snapshots.
- Release reused CRTC owners before staging output modes, then restore
  changed outputs before former owners when a transaction fails.
- Wait for resize-capture GPU completion, expand filtered surface
  damage, and preserve IME popup origin under fractional scaling.
- Mark weekends like holidays in both calendar layouts.

vendor/smithay/DCO.md

@@ -0,0 +1,34 @@
+Developer Certificate of Origin
+Version 1.1
+
+Copyright (C) 2026 Smithay maintainers
+
+Everyone is permitted to copy and distribute verbatim copies of this
+license document, but changing it is not allowed.
+
+
+Developer's Certificate of Origin 1.1
+
+By making a contribution to this project, I certify that:
+
+(a) The contribution was created in whole or in part by me and I
+    have the right to submit it under the open source license
+    indicated in the file; or
+
+(b) The contribution is based upon previous work that, to the best
+    of my knowledge, is covered under an appropriate open source
+    license and I have the right under that license to submit that
+    work with modifications, whether created in whole or in part
+    by me, under the same open source license (unless I am
+    permitted to submit under a different license), as indicated
+    in the file; or
+
+(c) The contribution was provided directly to me by some other
+    person who certified (a), (b) or (c) and I have not modified
+    it.
+
+(d) I understand and agree that this project and the contribution
+    are public and that a record of the contribution (including all
+    personal information I submit with it, including my sign-off) is
+    maintained indefinitely and may be redistributed consistent with
+    this project or the open source license(s) involved.