[25 MRG] Pydantic schema validation for species and samples

[TUPM96]

Bounty: 25 MRG

Validate species/sample JSON with pydantic; clear errors for missing care fields.

Acceptance

• Good/bad fixture tests

Claim (MergeOS MRG)

1. Star https://github.com/mergeos-bounties/PlantGuide and https://github.com/mergeos-bounties/mergeos
2. Comment on this issue: I claim this bounty
3. Comment on MergeOS Claim Token #1 with a link to this issue
4. Open a PR to PlantGuide (public product repo) with Fixes #<this-issue>

Policy: docs/BOUNTY.md

Important

Work lands on https://github.com/mergeos-bounties/PlantGuide.

Payout

Maintainer reviews PR → merge on PlantGuide → MRG credit on MergeOS ledger to github:<author> (25/50/100/200 scale).

[Zubi-fix]

/attempt #4

I can take this on. Going through the repo structure now and mapping out what needs to change. I'll push a PR when I'm confident the fix is clean and doesn't break anything else.

[code-cannot-be-blank]

/claim #4

I can get this done. Going through the codebase now — the issue looks clear enough. I'll put up a pull request shortly after I've validated the fix.

[elevasyncsolutions-jpg]

Claiming this bounty. Working on it now.

[laurentketterle-hub]

I claim this bounty

[laurentketterle-hub]

/claim

[ghzhost]

I claim this bounty

PR submitted: #423

Adds Pydantic v2 schema validation (SpeciesRecord, SampleRecord, CareCard) in src/plantguide/schemas.py with 18 tests covering good/bad fixtures and catalog integration.