…iteration (#6055)

* Refactor icon proxies for member caching and iteration

Introduced member caching in _CupertinoIconsProxy and _IconsProxy to avoid duplicate icon instances and improve attribute access. Added __iter__ and __len__ methods for both proxies to support iteration and length queries. Also set __name__ and __qualname__ for icon data classes to improve introspection.

* Update build version script to increment patch version

The script now increments the patch version instead of the minor version when updating the package version. This ensures versioning follows the semantic versioning convention more closely.

* Bump Flet to 0.80.4 and update Flutter to 3.38.7

Updated Flet package version to 0.80.4 and aligned Flutter version to 3.38.7. Changelogs updated to reflect refactoring of icon proxies and Flutter version bump. Adjusted PyPI cleanup script to match new versioning.

* flet-video: add mpv_properties to VideoConfiguration

* bugfix: fix compilation error for web

* docs: Improve mpv_properties documentation

* Update mpv_properties type hint and improve documentation for clarity

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Co-authored-by: ndonkoHenri <robotcoder4@protonmail.com>

* fix: allow Dropdown to expand horizontally (#6044)

* fix: apply ButtonStyle in TextButton (#6047)

* fix: TextButton style handling; allow Dropdown to expand horizontally

* fix(dropdown): correct expand logic

Co-authored-by: TheEthicalBoy <98978078+ndonkoHenri@users.noreply.github.com>

* fix(button): correctly resolve merged style without _internals

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Co-authored-by: TheEthicalBoy <98978078+ndonkoHenri@users.noreply.github.com>

Added entries for TextButton style and full-width Dropdown fix, mpv_properties in VideoConfiguration, and Icons/CupertinoIcons proxy refactor. Also included Flutter 3.38.7 update in both root and package changelogs.