Let a person and an organization hold more than one FileMaker code

[maebeale]

🤖 suggested review level: 3 Read 📖 one shared concern replacing a single-value assumption in a deduper, a merge, and five views

A person or organization can come from more than one FileMaker record, and the column already stores them comma-separated — but only Organization read it that way, so a person merge quietly threw one of the two codes away.

What is the goal of this PR and why is this important?

• The Rolodex import (Import people from the FileMaker Rolodex archive #2630) will hand one person several Rolodex IDs, and nothing downstream was ready for it.
• Three things were already wrong before that.

What was broken

• A person merge kept one code and dropped the other. Both are carried onto the keeper now, the way an org merge already does.
• PersonServices::DuplicateFinder clustered on the whole column, so 00006 and 00006, 00012 read as two people with conflicting codes instead of one shared code — the opposite of the truth.
• Five archive links assumed a single value (three person views, two org views). A record carrying two codes lost its link to the archive entirely and rendered as plain text.

How did you approach the change?

• FilemakerCoded — one concern, included by Person and Organization, owning #filemaker_codes and .join_filemaker_codes. The methods move off Organization, so there's no second copy.
• filemaker_code_links renders one archive link per code. They now open in a new tab (only one of the five did), so you keep your place on the record page.

Anything else to add?

• No migration and no backfill. A single code is just a one-element list, so existing rows read the same as before.

🤖 Generated with Claude Code