Backport of adds target aliases and transparent sessions usage docs into stable-website

[hc-github-team-secure-boundary]

Backport

This PR is auto-generated from #5243 to be assessed for backporting due to the inclusion of the label backport/website.

The below text is copied from the body of the original PR.

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Aliases and transparent sessions overview Aliases concepts page Transparent sessions concepts page

This PR adds usage docs for target aliases and transparent sessions.

• Adds new configuration/target-aliases book
  • Overview
  • Create target aliases
  • Connect to a target using an alias
  • Configure transparent sessions
• Migrates appropriate usage docs content from Concepts pages to the usage docs
• Adds a new configuration example for targets with a host ID specified

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Overview of commits

- f6d2d201297be47ccf1e2fe2d6dd06bf92177e3d - 1ce8ec2817fa9fc4af262dacb222cbd47dd480b7 - d4c02eb987bd534cb604796dcbd63b7645ce2878 - f94741c627ec1e21c0575ee50ad9293b1c12205b - 681bf7c36b5a5791e389766b6e7a201c133be809 - 04156a12037f38f7840bea7ff6f6951bc3cb1ead - ed173a4470f26f05585211262a58cf19f306d34c - 5cdf70444a284397daa8ada8ccd4779339d7a164 - 8845b7236ad072a404c811d3759c73c7762d106b - ecbb8aaf6e75f85c516a4bc6a5f939e432be183e - 571f8d054adef5fdc4e7b13539f4c21df14eccd5 - 73c43dd0b7e2740daa95a539bbf27924ce312865 - a63a66c1a07b1aefd35c995b3b73033d1968c794