Add comprehensive firmware upload documentation

[Copilot]

• Create comprehensive firmware upload documentation
  • Document prerequisites (tools and drivers)
  • Document uploading via PlatformIO (recommended for developers)
  • Document uploading via esptool.py (for prebuilt binaries)
  • Document uploading via Arduino IDE (alternative method)
  • Document how to obtain firmware binaries from GitHub releases and Actions
  • Add comprehensive troubleshooting section
• Update README.md with link to upload documentation
• Verify documentation is clear and accurate
• Merge dev branch with CI and library updates

Summary

Created a comprehensive 280-line firmware upload guide (FIRMWARE_UPLOAD.md) that covers:

• Three upload methods: PlatformIO, esptool.py, and Arduino IDE
• Prerequisites: Hardware and software requirements including CP210x drivers
• Step-by-step instructions for each method with platform-specific examples
• Multiple ways to obtain firmware: From source, GitHub releases, or Actions artifacts
• Troubleshooting section: Covers common issues like device detection, upload failures, port selection, and permissions
• Verification steps: How to confirm firmware is working correctly
• Additional resources: Links to relevant documentation

Updated README.md to include a new "Firmware Upload" section with a link to the detailed guide.

Merged Changes from dev branch

Merged the dev branch which includes:

• Updated GitHub Actions versions (checkout v2→v4, setup-python v1→v5, upload-artifact v2→v4)
• Updated ESP32Encoder library from v0.3.8 to v0.11.7
• Fixed ESP32Encoder API compatibility (UP → puType::up)

Original prompt

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This section details on the original issue you should resolve

<issue_title>Upload firmware documentation</issue_title>
<issue_description>Document how to upload project releases to the microcontroller</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #6

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[simonachmueller]

@copilot merge dev branch

[Copilot]

@copilot merge dev branch

Merged dev branch successfully in commit ee93539. The merge includes:

• GitHub Actions updates (checkout, setup-python, upload-artifact to latest versions)
• ESP32Encoder library update from v0.3.8 to v0.11.7
• API compatibility fix for ESP32Encoder