Feature Request: Add Canadian Business Number recognizer (CA_BN)

Is your feature request related to a problem? Please describe.

Presidio currently supports two Canadian entities (CA_SIN and CA_POSTAL_CODE) but not the Canadian Business Number (BN), a 9-digit business identifier issued by the Canada Revenue Agency (CRA). BNs appear in invoices, tax filings, payroll records, and B2B documents, so text containing them cannot currently be fully de-identified for Canadian business contexts.

Describe the solution you'd like

A new pattern recognizer, CaBnRecognizer, detecting the entity CA_BN:

• Format: 9 digits where the last digit is a Luhn check digit (same scheme as CA_SIN). Commonly written as a 15-character program account number: the 9-digit BN + a 2-letter CRA program identifier (RT, RP, RC, RM, RR, RZ) + a 4-digit reference number, e.g. 123456782 RT 0001.
• Detection: a weak pattern for the bare 9-digit form (relies on context words) and a medium pattern for the program account form, with Luhn checksum validation to eliminate false positives.
• Bilingual English/French context words (business number / numéro d'entreprise, CRA / ARC, GST / TPS, etc.).
• Registered disabled by default with en/fr support, following the CA_SIN and CA_POSTAL_CODE (#2204) precedents.

Reference: https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/business-registration/business-number-program-account/need-program-accounts.html

Describe alternatives you've considered

A deny-list or custom regex per deployment, but a predefined, checksum-validated recognizer benefits all users and matches how other national identifiers (AU_ABN, SG_UEN) are handled.

Additional context

I have a working implementation with unit tests ready and will open a PR referencing this issue.