Improve SSM Session Manager: Add SSH key injection and optimize code

[mayankgupta57]

• Add automatic SSH key injection via SSM before each connection
• Reuse existing code patterns from Instance Connect implementation
• Create reusable SSM command execution helper method
• Optimize SSH key injection with duplicate key prevention
• Update hostname to localhost when using SSM proxy command
• Update documentation to reflect SSH key injection functionality

Description

Please describe what this change achieves

Issues Resolved

The current implementation of ssm session manager is incomplete, it's not working, the connection get struck while using ssm:

exec bundle exec kitchen login --log-level=debug
D      [AWS SSM Session Manager] Setting up SSM Session Manager overrides
D      Policyfile found at /Users/mayankgu/git_corp/di_infra/cookbook-prometheus/Policyfile.rb, using Policyfile to resolve cookbook dependencies
       [AWS SSM Session Manager] Using proxy command: aws ssm start-session --target i-062f944081df579ff --region us-west-2 --profile oz-dev
D      Login command: ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o LogLevel=VERBOSE -o ProxyCommand=aws ssm start-session --target i-062f944081df579ff --region us-west-2 --profile abcd -p 22 root@179.22.130.5 (Options: {})

Type of Change

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The most important prefixes you should have in mind are:

• _fix_: which represents bug fixes, and correlates to a SemVer patch.
• _feat_: which represents a new feature, and correlates to a SemVer minor.
• _feat!_:, or fix!:, refactor!:, etc., which represent a breaking change (indicated by the !) and will result in a major version change.

If you have not included a conventional commit message this can be fixed on merge.

Check List

• New functionality includes tests
• All tests pass
• Commit message includes a Conventional Commit Message