fix(app): make composer input IME-safe and paste-aware (#3343)

* fix(app): preserve native composer input semantics

Native text was round-tripped through application state on every keystroke, which could overwrite an input method's in-flight edits. Keep native text ownership inside the input and reserve application-driven replacement for explicit draft mutations.\n\nRoute native clipboard images through the existing persisted attachment pipeline so keyboard and system paste actions behave like other image sources.

* fix(nix): refresh dependency hash

The native composer dependency changes the fixed npm dependency closure used by desktop builds.

* fix(app): keep composer locked across image pastes

Count concurrent native image persistence operations so submit remains disabled until every pasted image is attached.

* fix(app): replace composer text through the DOM on web

Web TextInput refs are DOM elements, so application-driven draft replacement must update their value and selection without native setNativeProps.

* fix(app): preserve web IME composition

Carry the Chinese IME fix from #2990 into the web composer input boundary.

Co-authored-by: Jimmy Lee <jimersylee+github@gmail.com>

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Co-authored-by: Jimmy Lee <jimersylee+github@gmail.com>

nix/npm-deps.hash

@@ -1 +1 @@
-sha256-i5PbVUe2Ec+GtghV9IpCJQJ9hcUT5hFhmxneNvoD584=
+sha256-qPIKchcbGkJHFSqgeM/BUSmu7TiVfKy3IEgUcMNNJYc=