refactor: update QR scanner instructions and improve config flow for …

[Kannix2005]

…local handling

[Copilot]

Pull request overview

This PR refactors the QR-scanner config flow to always use the QR scanner page served by the Home Assistant instance itself, and updates documentation accordingly while removing the legacy external-scanner constant.

Changes:

• Simplify config flow QR-scanner URL generation to always point at /api/siedle/qr_scanner on the selected HA base URL.
• Remove the external QR-scanner URL constant and references.
• Update EN/DE READMEs to describe the new QR-scanner behavior and HTTPS/camera constraints.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
custom_components/siedle/config_flow.py	Removes external-scanner fallback logic and builds a single local QR-scanner URL.
custom_components/siedle/const.py	Removes the external QR-scanner URL constant.
custom_components/siedle/fcm_handler.py	Removes a comment line above the Firebase configuration constant.
README.md	Updates QR-scanning instructions to match the new local-scanner flow.
README_DE.md	Updates German QR-scanning instructions to match the new local-scanner flow.

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[Copilot]

base_url = external or internal can select an HTTP external_url even when an HTTPS internal_url is available, which will prevent in-browser camera scanning despite HTTPS being configured. Consider preferring an HTTPS URL when either external_url or internal_url starts with https:// (and fall back otherwise).

Suggested change

	base_url = external or internal or "http://homeassistant.local:8123"
	# Prefer an HTTPS URL (internal or external) when available, fall back otherwise
	https_candidates = [url for url in (internal, external) if url and url.startswith("https://")]
	if https_candidates:
	base_url = https_candidates[0]
	else:
	base_url = external or internal or "http://homeassistant.local:8123"

[Copilot]

base_url may be configured with a trailing slash (user-provided internal/external URL). Concatenating with "/api/..." can produce a //api/... URL; strip the trailing slash (e.g., base_url.rstrip('/')) before building qr_scanner_url.

Suggested change

	base_url = external or internal or "http://homeassistant.local:8123"
	base_url = external or internal or "http://homeassistant.local:8123"
	base_url = base_url.rstrip("/")