qt6: add initial version for building and packaging base of Qt6 - #65

Checking PR #65: qt6: add initial version for building and packaging base of Qt6 (Makefile Audit Profile)

Commit 2a3b2e7 - qt6: add initial version for building and packaging base of Qt6:

✅ Makefile contains valid assignment operators and no spaces after ':='
✅ Makefile does not reuse PKG_NAME in call, define, or eval lines
✅ File additions contain clean UNIX (LF) line termination
✅ All modified files contain a trailing newline
❌ New OpenWrt package is missing the mandatory parameter: 'PKG_MAINTAINER'
❌ New OpenWrt package is missing the mandatory parameter: 'PKG_LICENSE'
❌ New OpenWrt package is missing the mandatory parameter: 'PKG_LICENSE_FILES'
❌ Makefile line 'DEPENDS+=+zlib +libzstd +libstdcpp +libpcre2-16 +libdouble-conversion $(ICONV_DEPENDS) +BUILD_qt6base-gui_ICU:icu #FIXME: do not include ICONV_DEPENDS if ICU is selected (though, that's only an issue when using GNU iconv)' inside 'Package/qt6base-core' must be indented with exactly 2 spaces
❌ Makefile line 'TITLE+=bearer (plugin)' inside 'Package/qt6base-plugin-bearer-generic' must be indented with exactly 2 spaces

Package Release Audit:

✅ New package frameworks/qt6/qt6base correctly initializes PKG_RELEASE to 1