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/UPSTREAM.md

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+# Vendored Smithay
+
+- Repository: https://github.com/Smithay/smithay
+- Revision: `8a270232f1bfc416c781273c98a3f52a812a0bba`
+- Source: complete tracked snapshot from `git archive --format=tar 8a270232f1bfc416c781273c98a3f52a812a0bba`. No `.git`, `target`, or untracked Cargo cache markers are included.
+- Original archive: 4894720 bytes; SHA-256 `81a42cfd4c3626c9bad8051023970151dcea0fe7bedd02fc09105db360a847c2`.
+- Original snapshot: 345 regular files; 4559959 content bytes. File contents, symlink targets and Git executable bits were independently verified against the archive. Archive ownership and write permissions follow the extracting user's normal umask.
+- Licenses are preserved in `LICENSE.txt`, `smithay-drm-extras/LICENSE`, and individual source headers.
+
+## Local patch
+
+`patches/shm-texture-cache-format.patch` changes the GLES SHM surface-cache compatibility check to match dimensions, GL internal format, and alpha interpretation. Previously an equal-sized ARGB/XRGB change reused stale `has_alpha`, selecting the wrong shader variant. A newly allocated texture also forces a complete upload. Context identity is already part of the cache key. Offset and stride describe each upload's source and are read anew; SHM cache entries always have normal orientation and non-external storage, so those properties do not add compatibility criteria.
+
+At most 16 debug records per process describe format incompatibilities. Records contain only numeric format/dimension fields, alpha booleans, and a fixed event message. They contain no pixel data, application text, titles, or credentials.
+
+The independent private-Wayland GPU regression is in Ferese's `compositor/src/state/partial_shm_gpu_tests.rs`. It compares the cached renderer with a new, unshared EGL context and full upload/full repaint on every frame, in both ARGB-first and XRGB-first directions. The ordinary partial-damage regression shares the fixture.
+