Release-prep for **v26.6.2**, a consolidated release rolling up the
26.6.1 feature wave, the v26.6.1.1 hotfixes, and new work through #3443.

Bumps version 26.6.1.1 → 26.6.2 in `CMakeLists.txt` and the `README.md`
banner, and prepends the v26.6.2 `CHANGELOG.md` entry. No code changes.

Headline content: runtime theming system, three HID controller classes
(StreamDeck+, Ulanzi Dial, Icom RC-28), the packet-radio suite
(KISS-over-TCP TNC #3279, connected-mode BBS terminal #3381, PMS
mailbox), and the Microsoft Store MSIX packaging path
(#3178/#3205/#3225/#3281).

💻 Generated with Claude Code (Opus 4.8) with architecture by @jensenpat

Co-authored-by: Codex <noreply@openai.com>

## Summary

This PR adds the first pass of Windows Store/MSIX packaging support for
AetherSDR.

- Adds `packaging/windows/create-msix.ps1` to generate an MSIX package
from the existing Windows `deploy` directory.
- Generates MSIX visual assets from the existing logo, writes
`AppxManifest.xml`, adds App Installer UX metadata, runs `makeappx.exe`,
optionally signs with `signtool.exe`, and can create a `.msixupload` for
Partner Center.
- Wires the Windows installer workflow to build unsigned MSIX/MSIXUPLOAD
artifacts alongside the portable zip and Inno installer.
- Adds repository variable hooks for Partner Center identity/display
values and package color options.
- Adds docs for local packaging, sideload signing, manifest values,
GitHub variables, and current WACK follow-ups.
- Ignores generated MSIX/package roots, deploy folders, local certs, and
related package artifacts.

## Current Manifest Defaults

- Display name: `AetherSDR`
- Publisher display name: `AetherSDR`
- Description: `Multi-platform SDR client for FlexRadio transceivers
(6000/8600/Aurora).`
- Minimum OS: Windows 10 2004 / build 19041
- Capabilities: `runFullTrust`, `internetClient`,
`privateNetworkClientServer`, `microphone`

Partner Center will still need to provide the final `Identity.Name` and
`Identity.Publisher` values.

## Validation

- PowerShell parser check passed for
`packaging/windows/create-msix.ps1`.
- `git diff --check` passed.
- Local MSVC/Qt build and unsigned MSIX generation were exercised
manually while developing this branch.
- Windows App Certification Kit was run locally; the docs now capture
the remaining follow-ups.

## Known Follow-Ups

- Replace the Windows support-bundle PowerShell `Compress-Archive` call
with in-process ZIP creation.
- Decide how to handle DFNR for Store packaging. The current
`DeepFilterNet3_onnx.tar.gz` archive triggers WACK archive checks;
`df_create(nullptr, ...)` may allow using the embedded default model
instead.
- Add PerMonitorV2 DPI awareness before final WACK/Store submission.
- Review Qt/vendor DLL blocked-executable warnings separately from
app-owned process-launch behavior.

---------

Co-authored-by: Codex <noreply@openai.com>
Co-authored-by: Jeremy Fielder <kk7gwy@aethersdr.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Release-prep for **v26.6.2**, a consolidated release rolling up the
26.6.1 feature wave, the v26.6.1.1 hotfixes, and new work through aethersdr#3443.

Bumps version 26.6.1.1 → 26.6.2 in `CMakeLists.txt` and the `README.md`
banner, and prepends the v26.6.2 `CHANGELOG.md` entry. No code changes.

Headline content: runtime theming system, three HID controller classes
(StreamDeck+, Ulanzi Dial, Icom RC-28), the packet-radio suite
(KISS-over-TCP TNC aethersdr#3279, connected-mode BBS terminal aethersdr#3381, PMS
mailbox), and the Microsoft Store MSIX packaging path
(aethersdr#3178/aethersdr#3205/aethersdr#3225/aethersdr#3281).

💻 Generated with Claude Code (Opus 4.8) with architecture by @jensenpat

Co-authored-by: Codex <noreply@openai.com>