Encoding trait

[MGibson1]

📔 Objective

Add encoding trait. This trait will reduce code as more types are convertable to/from EncString. Additionally, this common crate will be useful to define things like type-safe base64 encoded string types, which can then be used to explicitly define API expectations.

⏰ Reminders before review

• Contributor guidelines followed
• All formatters and local linters executed and passed
• Written new unit and / or integration tests where applicable
• Protected functional changes with optionality (feature flags)
• Used internationalization (i18n) for all UI strings
• CI builds passed
• Communicated to DevOps any deployment requirements
• Updated any necessary documentation (Confluence, contributing docs) or informed the documentation
  team

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[github-actions]

Checkmarx One – Scan Summary & Details – 34936b9c-6976-49f5-8978-7fa73546a5f7

Great job, no security vulnerabilities found in this Pull Request

[codecov]

Codecov Report

Attention: Patch coverage is 82.35294% with 6 lines in your changes missing coverage. Please review.

Project coverage is 65.67%. Comparing base (8d47784) to head (d9b8b39).

Files with missing lines	Patch %	Lines
crates/bitwarden-common/src/encoding.rs	75.00%	6 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #142      +/-   ##
==========================================
- Coverage   65.69%   65.67%   -0.03%     
==========================================
  Files         193      194       +1     
  Lines       14933    14941       +8     
==========================================
+ Hits         9810     9812       +2     
- Misses       5123     5129       +6     

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[Hinton]

Common is a really bad name and tells nothing about what it contains. Can this be a part of crypto or is it more generic than that?

[MGibson1]

@Hinton it's more generic. For this improvement, we could probably move to crypto, but eventually we should create a Base64 struct that explicitly marks a base64 encoded string. The same would be true of any non-utf8 encoded string data. That kind of thing would live in a common crate. However, if we're interested in a many-small-crates model, I could get behind something like bitwarden-encoding 🤷