Treat Stripe permission errors as invalid keys

[Amtron]

Summary

• is_valid_key now treats empty keys, publishable pk_ keys, and any stripe.error.StripeError (including PermissionError) as invalid instead of letting the exception abort the company save.
• Saving Stripe keys that Stripe will not accept for Charge.list no longer 500s; isStripeValid is set to false, or the existing 400 is returned if Stripe is already enabled.

Test plan

• Add a publishable key (pk_…) as the secret key and confirm the company save succeeds (or returns the existing 400 if Stripe is enabled), not a 500
• Add a restricted key without Charges read and confirm the same
• Add a valid sk_test_ / sk_live_ key matching company test/live mode and confirm isStripeValid is true
• Run python/tests/test_stripe_util.py

Made with Cursor

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