feat: add China Broadnet (中国广电) 1610 mobile number support

[ninjachen]

Description:

Summary

• Add 1610 number prefix as a valid mobile number pattern for China Broadnet (中国广电)
• Update carrier mapping data for en, zh, and zh_Hant locales
• Add unit test to verify 1610 numbers are recognized as valid Chinese mobile numbers

Background

China Broadnet (中国广电) is China's fourth telecom operator. The 192 prefix is already supported, but the 1610 prefix was missing from libphonenumber metadata. Here is the wiki page

Changes

• resources/PhoneNumberMetadata.xml — add 1610\d{7} to CN mobile pattern
• resources/carrier/en/86.txt — add 861610|China Broadnet
• resources/carrier/zh/86.txt — add 861610|中国广电
• resources/carrier/zh_Hant/86.txt — add 861610|中國廣電
• ExampleNumbersTest.java — add test testChinaBroadnet1610IsValidMobile

Test plan

• testChinaBroadnet1610IsValidMobile validates parsing and type detection

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