Add Bosch Twinguard support

[dehnerson]

Proposed change

Add complete Bosch Twinguard (8750001213, model Champion) support using the Quirks V2 API.

• Perform the Bosch-specific pairing handshake required to complete joining.
• Expose temperature, humidity, illuminance, battery, AQI/eCO2, smoke, self-test, sensitivity, pre-alarm, and heartbeat controls.
• Add Bosch-native alarm mode control (stop, pre_alarm, fire, and burglar) and read-only siren state feedback.
• Support both known manufacturer strings and suppress stale placeholder entities from the standard measurement clusters.

Fixes #2561.
Supersedes #3293 with a tested V2 implementation and full alarm/smoke support.

Additional information

The protocol behavior was independently implemented using the Zigbee2MQTT Twinguard implementation as a reference. The quirk has been manually tested with Home Assistant 2026.8.1 and a Connect ZBT-2, including fresh pairing, measurements, configuration controls, self-test, and all alarm modes.

The complete local suite reached 4,846 passed and 2 xfailed; the remaining 8 failures are unrelated Windows-specific failures in existing Inovelli path handling and Tuya timezone/request tests.

Device diagnostics

bosch-twinguard-diagnostics.json

Test plan

• Added tests for V2 matching, both manufacturer strings, entity metadata, scaling, and default-entity suppression
• Added tests for pairing bindings, handshake ordering, initial writes, and cache-priming reads
• Added tests for smoke/fire acknowledgements, reported alarm states, read-only siren state, and all alarm modes
• Ran pytest tests/test_bosch_twinguard.py tests/test_bosch.py tests/test_quirks_v2.py -q (23 passed)
• Ran pre-commit run --all-files

Checklist

• The changes are tested and work correctly
• pre-commit checks pass / the code has been formatted using Ruff
• Tests have been added to verify that the new code works
• Device diagnostics data has been attached

[codecov]

Codecov Report

❌ Patch coverage is 96.96970% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.66%. Comparing base (b139f81) to head (6793608).

Files with missing lines	Patch %	Lines
zhaquirks/bosch/twinguard.py	96.96%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              dev    #5250      +/-   ##
==========================================
+ Coverage   92.60%   92.66%   +0.06%     
==========================================
  Files         424      425       +1     
  Lines       14667    14832     +165     
==========================================
+ Hits        13582    13744     +162     
- Misses       1085     1088       +3     

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