fix(connections): skip password prompt for AWS IAM connections

[antoncazalet]

Summary

• AWS IAM connections prompted for a password on connect. IAM supplies the credentials, so the prompt was never needed and only blocked the connection flow.

Changes

• Gate the password prompt on !usesAWSIAM in the health-check reconnect path (DatabaseManager+Health) and in session creation (DatabaseManager+Sessions).
• Stop treating IAM connections as prompt-for-password in the connection form (ConnectionFormCoordinator).

Test plan

• Connect an AWS IAM (RDS) connection and confirm no password prompt appears.
• Confirm a normal prompt-for-password connection still prompts.
• Confirm an IAM connection auto-reconnects after a dropped session without prompting.

[github-actions]

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[antoncazalet]

I have read the CLA Document and I hereby sign the CLA.

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Avoid suppressing non-IAM test password prompts

This now treats every auth mode that hides the password as non-prompting, but auth.hidesPassword is also true for PostgreSQL usePgpass, not just AWS IAM. A normal UI path is to enable “Prompt for password”, then enable “Use ~/.pgpass”; the Test Connection path will stop prompting here and can pass using pgpass, while saving still persists promptForPassword and connectToSession only exempts AWS IAM, so the saved connection prompts anyway. Please gate this on the actual AWS IAM setting or clear/persist the prompt flag consistently for the other hidden-password modes.

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[datlechin]

Thank you.