Standardize dashAI branding across installers, bundles, and release artifacts

[Irozuku]

Summary

Rebrands the desktop app from DashAI to dashAI across packaging (PyInstaller spec, Inno Setup installer) and the release CI workflow, and gives the app a real icon. Replaces the old installer icon with the dashAI isotype and sets that icon on both the Windows .exe and the macOS .app bundle (previously had none). All release artifacts, installers, DMGs, and the publisher name are renamed to dashAI for consistent branding.

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Type of Change

• Backend change
• Frontend change
• CI / Workflow change
• Build / Packaging change
• Bug fix
• Documentation

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Changes (by file)

• installer/installer.iss: rename user visible strings (AppName, AppPublisher, DefaultDirName, DefaultGroupName, OutputBaseFilename, shortcut names, launch description) to dashAI; point SetupIconFile to the new icon; update launcher exe/path references to dashAI-launcher-cpu.
• installer/dashAI.ico: new installer icon (dashAI isotype, multi size 16-256px), replacing DashAI.ico.
• installer/dashAI.icns: new macOS icon generated from the same isotype.
• dashai.spec: rename app bundle to dashAI.app and launcher to dashAI-launcher-cpu; set icon on the EXE (dashAI.ico) and BUNDLE (dashAI.icns).
• .github/workflows/publish.yml: update build output paths (dist/dashAI.app, dashAI-Installer.exe) and rename all release artifacts, DMGs, and asset names (dashAI-windows-installer, dashAI-dmg-arm64/x86_64, dashAI-macos-*.dmg, dashAI-${V}-* release files) so signing, DMG creation, uploads, and release staging stay consistent.

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Testing

• Windows: run pyinstaller --clean --noconfirm dashai.spec, then & "C:\Program Files (x86)\Inno Setup 6\ISCC.exe" .\installer\installer.iss. Confirm the icon shows on dashAI-launcher-cpu.exe and the installer is produced as dashAI-Installer.exe.
• macOS: build the spec and confirm dist/dashAI.app carries the icon and the DMG builds.

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Notes

• Source tree paths (DashAI/front/...) are unchanged.
• bundle_identifier=com.dashai.app left as is (already lowercase, not user facing).