feat: add support for migration of firebase scrypt passwords

[J0]

What kind of change does this PR introduce?

Fix #1750. Firebase uses a modified version of scrypt We add support for Firebase Scrypt hashes so that developers can move over from Firebase (or similar) without the obligation to force a password reset for all users.

As there is no pre-defined convention for Firebase scrypt hashes, we establish the following:

$fbscrypt$v=1,n=<N>,r=<r>,p=<p>,ss=<salt_separator>,sk=<signer_key>$<salt>$<hash>

$fbscrypt: Firebase scrypt Identifier
$v: version identifier. Intended to allow for flexibility in parameters used.
$n: N is the CPU/memory cost parameter.
$r: block size
$p: parallelization
$ss: salt seperator, optional, only if using firebase,  base64-encoded string used to separate the salt from other parameters.
$sk: signer key, a base64-encoded string used as an additional input to the hash function.
$<salt>: base64 encoded salt
$<hash>: base64 encoded output

Developers can extract their hash parameters from the firebase console

For testing and debugging, clone this utility and follow the instructions in BUILDING.

On MacOS please add the following flags when attempting to build so as to guard against error: AES_FUNCTION missing

export CFLAGS="-I$(brew --prefix openssl)/include"
export LDFLAGS="-L$(brew --prefix openssl)/lib -L/usr/local/opt/openssl/lib"

More details about export from CLI

[hf]

Would prefer if the name for the Firebase scrypt be fbscrypt instead of scrypt.

[coveralls]

Pull Request Test Coverage Report for Build 11048130786

Details

• 91 of 121 (75.21%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 57.916%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
internal/crypto/password.go	85	115	73.91%

Totals
Change from base Build 11017821166:	0.1%
Covered Lines:	9332
Relevant Lines:	16113

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💛 - Coveralls

[hf]

Looks good! Thanks!