streamdeck_read_profiles fails on Windows with UTF-8 profile/page manifests

[kodroi]

Summary

On Windows, streamdeck_read_profiles can fail with:

UnicodeDecodeError: ''charmap'' codec can''t decode byte 0x8d ...

when any Stream Deck profile or page manifest.json contains non-ASCII UTF-8 content such as emoji.

Reproduction

1. Create or edit a Stream Deck profile page so a page manifest contains UTF-8 text, for example: "pastedText": "👍"
2. Run the MCP server via uvx streamdeck-mcp
3. Call streamdeck_read_profiles

Actual

The server crashes while reading profile/page manifests on Windows with a charmap / cp1252 decode error.

Expected

Profile and page manifests should load successfully regardless of UTF-8 content.

Root cause

profile_manager.py reads profile JSON with Path.read_text() without specifying an encoding, so Windows uses the process default ANSI codepage instead of UTF-8.

Affected helper:

• _load_json(path) -> json.loads(path.read_text())

Proposed fix

Read and write profile manifests explicitly as UTF-8:

• path.read_text(encoding="utf-8")
• write_text(..., encoding="utf-8")

Notes

I reproduced this against a real Stream Deck profile where a page manifest contained "pastedText": "👍", and confirmed the failure occurs in streamdeck_read_profiles while building page refs.